Provided is a seat adjustment device which is capable of suppressing wobbling of first and second plates and a planetary gear. The seat adjustment device (10) comprises: a first plate (1) provided with a first gear section (12); a second plate (2) provided...

Provided is a seat adjustment device which is capable of suppressing wobbling between internal teeth of a plate, and external teeth of planetary gears. The seat adjustment device comprises a holding member (500A) holds at least one (3a) of the planetary ge...