Abstract: The provided is a rotational speed detection structure of an actuator and an actuator. The rotational speed detection structure of an actuator includes an outer housing, a motor, and a reducer mechanism, where the motor includes a stator and a rotor; a shaft sleeve is connected to the rotor; the reducer mechanism includes an input end connected to the rotor, and an output end connected to an encoder shaft; a first mounting surface is disposed on the encoder shaft; a second mounting surface is disposed on the shaft sleeve; a first magnetic ring is fixed on the first mounting surface; a second magnetic ring is fixed on the second mounting surface; a printed circuit board (PCB) is fixed on the outer housing; the PCB includes a third mounting surface; a first Hall element and a second Hall element are provided on the third mounting surface.