https://newnuclearjobs.com/roles/mechanical-engineer/ 71 open mechanical engineer roles at 15 advanced nuclear companies, most at Antares (13), Kairos Power (10) and Valar Atomics (10). Updated daily. en Tue, 10 Nov 2026 00:00:00 GMT https://newnuclearjobs.com/jobs/staff-mechanical-engineer-numenor-reactor-valar-atomics-cd9a13/https://newnuclearjobs.com/jobs/staff-mechanical-engineer-numenor-reactor-valar-atomics-cd9a13/Mon, 09 Nov 2026 00:00:00 GMTValar Atomics has an open Staff Mechanical Engineer, Numenor (Reactor) position. The role is based in Torrance, California, United States. https://newnuclearjobs.com/jobs/senior-mechanical-engineer-numenor-reactor-valar-atomics-8f2661/https://newnuclearjobs.com/jobs/senior-mechanical-engineer-numenor-reactor-valar-atomics-8f2661/Mon, 09 Nov 2026 00:00:00 GMTValar Atomics is looking for a Senior Mechanical Engineer, Numenor (Reactor). The role is based in Torrance, California, United States. https://newnuclearjobs.com/jobs/director-of-mechanical-engineering-numenor-reactor-valar-atomics-e9b641/https://newnuclearjobs.com/jobs/director-of-mechanical-engineering-numenor-reactor-valar-atomics-e9b641/Mon, 09 Nov 2026 00:00:00 GMTValar Atomics is hiring a Director of Mechanical Engineering, Numenor (Reactor). The role is based in Torrance, California, United States. https://newnuclearjobs.com/jobs/manager-mechanical-design-valar-atomics-1f997c/https://newnuclearjobs.com/jobs/manager-mechanical-design-valar-atomics-1f997c/Mon, 09 Nov 2026 00:00:00 GMTValar Atomics has an open Manager, Mechanical Design position. The role is based in Torrance, California, United States. https://newnuclearjobs.com/jobs/mechanical-engineer-fuel-handling-equipment-kairos-power-121c62/https://newnuclearjobs.com/jobs/mechanical-engineer-fuel-handling-equipment-kairos-power-121c62/Thu, 05 Nov 2026 00:00:00 GMTKairos Power is hiring a Mechanical Engineer, Fuel Handling Equipment on its Pebble Handling and Storage System team. The role is based in Alameda, CA. https://newnuclearjobs.com/jobs/principal-mechanical-engineer-fuel-handling-equipment-kairos-power-146f61/https://newnuclearjobs.com/jobs/principal-mechanical-engineer-fuel-handling-equipment-kairos-power-146f61/Fri, 30 Oct 2026 00:00:00 GMTKairos Power has an open Principal Mechanical Engineer, Fuel Handling Equipment position on its Pebble Handling and Storage System team. The role is based in Oakridge, Tennessee. https://newnuclearjobs.com/jobs/lead-mechanical-designer-turbomachinery-valar-atomics-218897/https://newnuclearjobs.com/jobs/lead-mechanical-designer-turbomachinery-valar-atomics-218897/Thu, 29 Oct 2026 00:00:00 GMTValar Atomics has an open Lead Mechanical Designer, Turbomachinery position on its Power Conversion team. The role is based in Torrance, California, United States. https://newnuclearjobs.com/jobs/mechanical-maintenance-planner-valar-atomics-242a0e/https://newnuclearjobs.com/jobs/mechanical-maintenance-planner-valar-atomics-242a0e/Thu, 29 Oct 2026 00:00:00 GMTValar Atomics has an open Mechanical Maintenance Planner position on its Utah Site Operations team. The role is based in Orangeville, Utah, United States. https://newnuclearjobs.com/jobs/thermo-mechanical-engineer-heat-exchanger-antares-be26e4/https://newnuclearjobs.com/jobs/thermo-mechanical-engineer-heat-exchanger-antares-be26e4/Thu, 29 Oct 2026 00:00:00 GMTAntares has an open Thermo-Mechanical Engineer, Heat Exchanger position on its Reactor Hardware Engineering team. The role is based in Los Angeles. https://newnuclearjobs.com/jobs/senior-mechanical-design-engineer-pcs-antares-6f5b3b/https://newnuclearjobs.com/jobs/senior-mechanical-design-engineer-pcs-antares-6f5b3b/Wed, 28 Oct 2026 00:00:00 GMTAntares has an open Senior Mechanical Design Engineer (PCS) position on its Reactor Hardware Engineering team. The role is based in Los Angeles. https://newnuclearjobs.com/jobs/senior-mechanical-engineer-fuels-program-kairos-power-b64d7f/https://newnuclearjobs.com/jobs/senior-mechanical-engineer-fuels-program-kairos-power-b64d7f/Wed, 28 Oct 2026 00:00:00 GMTKairos Power is looking for a Senior Mechanical Engineer, Fuels Program. The role is based in Albuquerque, NM. https://newnuclearjobs.com/jobs/senior-mechanical-engineer-structures-radiant-46734d/https://newnuclearjobs.com/jobs/senior-mechanical-engineer-structures-radiant-46734d/Wed, 28 Oct 2026 00:00:00 GMTRadiant is looking for a Senior Mechanical Engineer, Structures. The role is based in El Segundo, CA. https://newnuclearjobs.com/jobs/senior-thermo-mechanical-engineer-heat-exchanger-antares-498113/https://newnuclearjobs.com/jobs/senior-thermo-mechanical-engineer-heat-exchanger-antares-498113/Wed, 28 Oct 2026 00:00:00 GMTAntares has an open Senior Thermo-Mechanical Engineer, Heat Exchanger position on its Reactor Hardware Engineering team. The role is based in Los Angeles. https://newnuclearjobs.com/jobs/senior-mechanical-design-engineer-space-antares-47cd5a/https://newnuclearjobs.com/jobs/senior-mechanical-design-engineer-space-antares-47cd5a/Mon, 26 Oct 2026 00:00:00 GMTAntares has an open Senior Mechanical Design Engineer - Space position. The role is based in Los Angeles. https://newnuclearjobs.com/jobs/mechanical-design-engineer-i-ii-space-antares-c8ec35/https://newnuclearjobs.com/jobs/mechanical-design-engineer-i-ii-space-antares-c8ec35/Mon, 26 Oct 2026 00:00:00 GMTAntares has an open Mechanical Design Engineer I/II - Space position. The role is based in Los Angeles. https://newnuclearjobs.com/jobs/mechanical-engineer-hvac-and-plumbing-systems-kairos-power-93cd74/https://newnuclearjobs.com/jobs/mechanical-engineer-hvac-and-plumbing-systems-kairos-power-93cd74/Thu, 22 Oct 2026 00:00:00 GMTKairos Power has an open Mechanical Engineer - HVAC and Plumbing Systems position on its Construction Projects team. The role is based in Albuquerque, NM. https://newnuclearjobs.com/jobs/mechanical-operator-standard-nuclear-c279f7/https://newnuclearjobs.com/jobs/mechanical-operator-standard-nuclear-c279f7/Tue, 20 Oct 2026 00:00:00 GMTStandard Nuclear is hiring a Mechanical Operator. The role is based in Idaho Falls, ID. https://newnuclearjobs.com/jobs/senior-mechanical-engineer-nusano-bafc00/https://newnuclearjobs.com/jobs/senior-mechanical-engineer-nusano-bafc00/Tue, 20 Oct 2026 00:00:00 GMTNusano is looking for a Senior Mechanical Engineer. The role is based in West Valley City, UT. https://newnuclearjobs.com/jobs/staff-mechanical-engineer-valar-atomics-66a58a/https://newnuclearjobs.com/jobs/staff-mechanical-engineer-valar-atomics-66a58a/Fri, 16 Oct 2026 00:00:00 GMTValar Atomics is hiring a Staff Mechanical Engineer. The role is based in Torrance, California, United States. https://newnuclearjobs.com/jobs/senior-mechanical-engineer-valar-atomics-f21c74/https://newnuclearjobs.com/jobs/senior-mechanical-engineer-valar-atomics-f21c74/Mon, 12 Oct 2026 00:00:00 GMTValar Atomics has an open Senior Mechanical Engineer position. The role is based in Torrance, California, United States. https://newnuclearjobs.com/jobs/mechanical-technician-process-gas-systems-valar-atomics-36e0e3/https://newnuclearjobs.com/jobs/mechanical-technician-process-gas-systems-valar-atomics-36e0e3/Fri, 09 Oct 2026 00:00:00 GMTValar Atomics is looking for a Mechanical Technician, Process Gas Systems on its Machine Shop team. The role is based in Torrance, California, United States. https://newnuclearjobs.com/jobs/mechanical-engineer-fuel-handling-equipment-kairos-power-994528/https://newnuclearjobs.com/jobs/mechanical-engineer-fuel-handling-equipment-kairos-power-994528/Fri, 09 Oct 2026 00:00:00 GMTKairos Power has an open Mechanical Engineer, Fuel Handling Equipment position on its Pebble Handling and Storage System team. The role is based in Albuquerque, New Mexico. https://newnuclearjobs.com/jobs/skillbridge-program-mechanical-technologist-kairos-power-11c765/https://newnuclearjobs.com/jobs/skillbridge-program-mechanical-technologist-kairos-power-11c765/Tue, 06 Oct 2026 00:00:00 GMTKairos Power is looking for a Skillbridge Program: Mechanical Technologist on its Pre-commissioning, Installation, Testing & Assembly team. The role is based in Albuquerque, NM. https://newnuclearjobs.com/jobs/principal-mechanical-engineer-blue-energy-60143a/https://newnuclearjobs.com/jobs/principal-mechanical-engineer-blue-energy-60143a/Fri, 02 Oct 2026 00:00:00 GMTBlue Energy has an open Principal Mechanical Engineer position. The role is hybrid, based in DC - Chevy Chase, MD. https://newnuclearjobs.com/jobs/senior-mechanical-systems-licensing-engineer-kairos-power-41465c/https://newnuclearjobs.com/jobs/senior-mechanical-systems-licensing-engineer-kairos-power-41465c/Wed, 30 Sep 2026 00:00:00 GMTKairos Power is looking for a Senior Mechanical Systems Licensing Engineer. The role is based in Alameda, CA, Albuquerque, NM or Oakridge, TN. https://newnuclearjobs.com/jobs/senior-mechanical-engineer-fuels-program-kairos-power-f43159/https://newnuclearjobs.com/jobs/senior-mechanical-engineer-fuels-program-kairos-power-f43159/Tue, 29 Sep 2026 00:00:00 GMTKairos Power is hiring a Senior Mechanical Engineer, Fuels Program. The role is based in Albuquerque, NM. https://newnuclearjobs.com/jobs/site-design-engineering-lead-mechanical-engineer-terrapower-f37a43/https://newnuclearjobs.com/jobs/site-design-engineering-lead-mechanical-engineer-terrapower-f37a43/Mon, 21 Sep 2026 00:00:00 GMTTerraPower has an open Site Design Engineering Lead Mechanical Engineer position on its Natrium team. The role is based in Kemmerer, Wyoming, United States. https://newnuclearjobs.com/jobs/space-mechanical-design-engineering-intern-summer-2027-antares-b718dd/https://newnuclearjobs.com/jobs/space-mechanical-design-engineering-intern-summer-2027-antares-b718dd/Fri, 18 Sep 2026 00:00:00 GMTAntares is hiring a Space Mechanical Design Engineering Intern - Summer 2027. The role is based in Los Angeles. https://newnuclearjobs.com/jobs/mechanical-test-optomechanical-systems-general-matter-96dfca/https://newnuclearjobs.com/jobs/mechanical-test-optomechanical-systems-general-matter-96dfca/Thu, 17 Sep 2026 00:00:00 GMTGeneral Matter is looking for a Mechanical Test, Optomechanical Systems on its Hardware Engineering team. The role is based in Los Angeles, CA. https://newnuclearjobs.com/jobs/mechanical-engineer-optomechanical-systems-general-matter-774526/https://newnuclearjobs.com/jobs/mechanical-engineer-optomechanical-systems-general-matter-774526/Thu, 17 Sep 2026 00:00:00 GMTGeneral Matter is hiring a Mechanical Engineer, Optomechanical Systems on its Hardware Engineering team. The role is based in Los Angeles, CA. https://newnuclearjobs.com/jobs/senior-mechanical-engineer-oklo-992ffe/https://newnuclearjobs.com/jobs/senior-mechanical-engineer-oklo-992ffe/Wed, 16 Sep 2026 00:00:00 GMTOklo is hiring a Senior Mechanical Engineer on its Fuel Recycling team. The role is remote-friendly; the listed location is Oak Ridge, TN or Remote. https://newnuclearjobs.com/jobs/mechanical-engineer-standard-nuclear-db0026/https://newnuclearjobs.com/jobs/mechanical-engineer-standard-nuclear-db0026/Tue, 15 Sep 2026 00:00:00 GMTStandard Nuclear is looking for a Mechanical Engineer. The role is based in Oak Ridge, TN. https://newnuclearjobs.com/jobs/senior-mechanical-engineer-hexium-4303f5/https://newnuclearjobs.com/jobs/senior-mechanical-engineer-hexium-4303f5/Fri, 11 Sep 2026 00:00:00 GMTHexium is looking for a Senior Mechanical Engineer on its Technology team. The role is based in Livermore, CA. https://newnuclearjobs.com/jobs/mechanical-engineering-design-intern-summer-2027-antares-5566d1/https://newnuclearjobs.com/jobs/mechanical-engineering-design-intern-summer-2027-antares-5566d1/Thu, 10 Sep 2026 00:00:00 GMTAntares has an open Mechanical Engineering Design Intern - Summer 2027 position. The role is based in Los Angeles. https://newnuclearjobs.com/jobs/staff-mechanical-engineer-the-nuclear-company-bd6369/https://newnuclearjobs.com/jobs/staff-mechanical-engineer-the-nuclear-company-bd6369/Tue, 01 Sep 2026 00:00:00 GMTThe Nuclear Company is hiring a Staff Mechanical Engineer on its Nuclear Engineering team. The role is based in Columbia, South Carolina. https://newnuclearjobs.com/jobs/summer-2027-internship-mechanical-engineering-hvac-general-matter-3eae87/https://newnuclearjobs.com/jobs/summer-2027-internship-mechanical-engineering-hvac-general-matter-3eae87/Tue, 01 Sep 2026 00:00:00 GMTGeneral Matter has an open Summer 2027 Internship - Mechanical Engineering (HVAC) position. The role is based in Los Angeles, CA. https://newnuclearjobs.com/jobs/mechanical-design-engineer-ii-reactivity-controls-antares-24b8d4/https://newnuclearjobs.com/jobs/mechanical-design-engineer-ii-reactivity-controls-antares-24b8d4/Thu, 27 Aug 2026 00:00:00 GMTAntares is looking for a Mechanical Design Engineer II - Reactivity Controls on its Reactor Hardware Engineering team. The role is based in Los Angeles. https://newnuclearjobs.com/jobs/senior-mechanical-design-engineer-reactivity-controls-antares-49b594/https://newnuclearjobs.com/jobs/senior-mechanical-design-engineer-reactivity-controls-antares-49b594/Thu, 27 Aug 2026 00:00:00 GMTAntares is looking for a Senior Mechanical Design Engineer - Reactivity Controls on its Reactor Hardware Engineering team. The role is based in Los Angeles. https://newnuclearjobs.com/jobs/mechanical-design-engineer-ii-pcs-antares-36fc73/https://newnuclearjobs.com/jobs/mechanical-design-engineer-ii-pcs-antares-36fc73/Mon, 24 Aug 2026 00:00:00 GMTAntares is looking for a Mechanical Design Engineer II (PCS) on its Reactor Hardware Engineering team. The role is based in Los Angeles. https://newnuclearjobs.com/jobs/thermo-mechanical-engineer-ii-antares-f5ce27/https://newnuclearjobs.com/jobs/thermo-mechanical-engineer-ii-antares-f5ce27/Wed, 19 Aug 2026 00:00:00 GMTAntares is looking for a Thermo-Mechanical Engineer II on its Reactor Hardware Engineering team. The role is based in Los Angeles. https://newnuclearjobs.com/jobs/senior-thermo-mechanical-engineer-antares-d979fb/https://newnuclearjobs.com/jobs/senior-thermo-mechanical-engineer-antares-d979fb/Wed, 19 Aug 2026 00:00:00 GMTAntares has an open Senior Thermo-Mechanical Engineer position on its Reactor Hardware Engineering team. The role is based in Los Angeles. https://newnuclearjobs.com/jobs/mechanical-engineer-new-grad-general-matter-e8e693/https://newnuclearjobs.com/jobs/mechanical-engineer-new-grad-general-matter-e8e693/Wed, 12 Aug 2026 00:00:00 GMTGeneral Matter is looking for a Mechanical Engineer (New Grad) on its Hardware Engineering team. The role is based in Los Angeles, CA. https://newnuclearjobs.com/jobs/mechanical-engineer-electronics-packaging-antares-3f72ca/https://newnuclearjobs.com/jobs/mechanical-engineer-electronics-packaging-antares-3f72ca/Tue, 11 Aug 2026 00:00:00 GMTAntares is looking for a Mechanical Engineer - Electronics Packaging on its Reactor Hardware Engineering team. The role is based in Los Angeles. https://newnuclearjobs.com/jobs/mechanical-design-engineer-power-conversion-valar-atomics-e7f762/https://newnuclearjobs.com/jobs/mechanical-design-engineer-power-conversion-valar-atomics-e7f762/Thu, 06 Aug 2026 00:00:00 GMTValar Atomics has an open Mechanical Design Engineer, Power Conversion position. The role is based in Torrance, California, United States. https://newnuclearjobs.com/jobs/mechanical-engineer-nusano-de7552/https://newnuclearjobs.com/jobs/mechanical-engineer-nusano-de7552/Wed, 29 Jul 2026 00:00:00 GMTNusano has an open Mechanical Engineer position. The role is based in West Valley City, UT. https://newnuclearjobs.com/jobs/mechanical-and-manufacturing-engineering-internship-summer-2027-kairos-1cbefe/https://newnuclearjobs.com/jobs/mechanical-and-manufacturing-engineering-internship-summer-2027-kairos-1cbefe/Thu, 23 Jul 2026 00:00:00 GMTKairos Power is looking for a Mechanical and Manufacturing Engineering Internship - Summer 2027. The role is based in Alameda, CA, Albuquerque, NM, or Oak Ridge, TN. https://newnuclearjobs.com/jobs/senior-mechanical-designer-fuel-recycling-oklo-c3e3d1/https://newnuclearjobs.com/jobs/senior-mechanical-designer-fuel-recycling-oklo-c3e3d1/Sun, 19 Jul 2026 00:00:00 GMTOklo is looking for a Senior Mechanical Designer - Fuel Recycling. The role is remote-friendly; the listed location is Oak Ridge, TN or Remote. https://newnuclearjobs.com/jobs/mechanical-engineer-components-forge-atomics-614a6e/https://newnuclearjobs.com/jobs/mechanical-engineer-components-forge-atomics-614a6e/Fri, 17 Jul 2026 00:00:00 GMTForge Atomics is looking for a Mechanical Engineer, Components. The role is based in El Segundo. https://newnuclearjobs.com/jobs/mechanical-engineer-reactor-structures-forge-atomics-2b4857/https://newnuclearjobs.com/jobs/mechanical-engineer-reactor-structures-forge-atomics-2b4857/Fri, 17 Jul 2026 00:00:00 GMTForge Atomics has an open Mechanical Engineer, Reactor Structures position. The role is based in El Segundo. https://newnuclearjobs.com/jobs/mechanical-engineer-fluids-forge-atomics-e4445a/https://newnuclearjobs.com/jobs/mechanical-engineer-fluids-forge-atomics-e4445a/Fri, 17 Jul 2026 00:00:00 GMTForge Atomics is looking for a Mechanical Engineer, Fluids. The role is based in El Segundo.