The earthquake-resistant test for the SDQH25 and SDQH50 type nuclear-grade valve electric actuator was introduced． For the tests using an earthquake simulating shaking table and adopting the multi-frequency test, the tests were controlled with using manual simulated acceleration time-histories, which based on the required response spectrum. The dynamic characteristics detect tests on the SDQH25 and SDQH50 type nuclear-grade valve electric actuator were carried out, and OBE (operational base earthquake) earthquake simulation test five times and the SSE (safety shutdown earthquake) earthquake simulation test one time. These tests prove that the SDQH25 and SDQH50 type nuclear-grade valve electric actuator can work normally under the effect of earthquake load．