A small-sized, front-end module is offered which is for use in a wireless communication device such as a mobile phone and which can suppress harmonics to a sufficiently low level. The front-end module has at least a switching circuit for switching one antenna between a transmiting system and a receiving system, a power amplifier for power-amplifying a transmission signal, and a low-pass filter inserted between the switching circuit and power amplifier. These components are integrated. A first kind of harmonics is produced from the switching circuit toward the power amplifier and reflected by the low-pass filter. A second kind of harmonics is produced from the power amplifier toward the antenna. A third kind of harmonics is produced from the switching circuit toward the antenna. The third kind of harmonics is canceled by the reflected first kind of harmonics and the second kind of harmonics.