There is provided a condenser microphone that has improved portability and that can be realized at low costs. The condenser microphone includes, as all being accommodated within a cylindrical housing, a capacitor including a diaphragm electrode and a fixed electrode, a signal processing circuit board disposed at one opening of the cylindrical housing and having a converter circuit for converting a change in capacitance of the capacitor which has occurred in association with vibration of the diaphragm electrode into an electric signal and outputting this electric signal, a gate ring disposed between the capacitor and the signal processing circuit board for establishing electric conduction therebetween, a switch circuit board disposed at the other opening of the cylindrical housing and having a switch for controlling operation of the converter circuit, and a drain ring disposed between the switch circuit board and the signal processing circuit board for transmitting a switch signal according to an operation of the switch to the signal processing circuit board.