A gate wiring electrode is formed into a ladder-like pattern. Moreover, between source electrodes and drain electrodes in the entire Switch MMIC, the gate wiring electrodes are disposed. Furthermore, at a cross part between the gate wiring electrode and the source electrode or the drain electrode, a nitride film having a large relative dielectric constant and a polyimide or a hollow part having a small relative dielectric constant are disposed. Accordingly, a capacitance at the cross part is reduced. Thus, a second harmonic wave level can be lowered. Moreover, a leak of a high-frequency signal between the drain electrode and the source electrode can be prevented. Thus, a third harmonic level can be lowered. Consequently, distortion characteristics of the Switch MMIC can be significantly improved.