In a side-entry condenser microphone, noise is prevented effectively from being generated by electromagnetic waves coming from the outside. In a side-entry condenser microphone including a metallic head case portion 10 which is covered with a metallic guard net 12 at an upper part thereof and is formed into a substantially cylindrical shape in which a microphone unit 13 is arranged via support members 14a and 14b in an internal space, and a metallic body portion 20 for supporting the head case portion 10 at the upper end thereof, a circuit board 21 mounted with an audio output circuit including an impedance converter is fitted in a lower opening of the head case portion 10 supported on the body portion 20 so as to close the lower opening with the circuit mounting surface 21a of the circuit board 21 being on the case inner surface side. Thereby, an electrostatic shield is completed by the head case portion 10 only.