A circuit module for a silicon condenser microphone of the present disclosure includes a transducer, a charge pump, an isolator, a first amplifier, a second amplifier, a reaction circuit, a first bias circuit, and a second bias circuit. The charge pump electrically connects to an input port of the transducer, and an output port of the transducer electrically connects to an input port of the first amplifier via the isolator. An output port of the first amplifier electrically connects to an input port of the second amplifier. The reaction circuit is arranged between the output port of the first amplifier and the input port of the transducer. The isolator isolates the direct-current components of the first electrical signal, and therefore, the oscillations of the direct-current components will not affect the performance of the first amplifier.