A micro electro-mechanical system (MEMS) circuit includes a MEMS differential capacitor, a read-out circuit, a control circuit, and a compensation circuit. The MEMS differential capacitor includes a first capacitor and a second capacitor. The read-out circuit is coupled to the MEMS differential capacitor for reading a difference between the first capacitor and the second capacitor in a zero-G condition, and generating an output signal according to the difference. The control circuit is coupled to the read-out circuit for receiving the output signal and generating a control signal. The compensation circuit is coupled to the control circuit for compensating the MEMS differential capacitor according to the control signal.