A MEMS actuator includes: a drive circuit for applying a drive voltage having a time waveform, which periodically repeats rising and falling and includes a period to be a constant voltage after the rising and before the falling, between a fixed comb electrode and a movable comb electrode; and a timing detection circuit that generates a capacitance derivative signal indicating a derivative value of a capacitance between the fixed comb electrode and the movable comb electrode by converting a current signal, which is output from the fixed comb electrode or the movable comb electrode within the period due to a change in the capacitance, into a voltage signal and detects a timing when the capacitance derivative signal reaches a threshold value. The drive circuit controls a relationship between the timing detected by the timing detection circuit and a timing of the falling to be constant.