The invention provides a high-frequency module which suppresses degradation of amplification characteristics of a power amplifier. The radio-frequency module (1) includes: a transmission power amplifier (11) that includes first and second amplification transistors (110P, 110D) that are cascade connected to each other; and a mounting substrate (90) that has first and second main surface (90a, 90b)that face each other, the transmission power amplifier (11) being mounted on the first main surface (90a). The first amplification transistor (110P) is arranged in a final stage and has a first emitter terminal (112P). The second amplification transistor (110D) is arranged in a stage preceding the first amplification transistor (110P) and has a second emitter terminal (112D). The mounting substrate (90) has first to fourth ground electrode layers (93g-96g) in order of proximity to the first main surface (90A). The first emitter terminal (112P) and the second emitter terminal (112D) are not electrically connected to each other via an electrode on the first main surface (90a) and are not electrically connected to each other via the first ground electrode layer (93g).