A directional coupler includes a main line, a first sub-line to be electromagnetically coupled to the main line, a second sub-line to be electromagnetically coupled to the main line, and a coupling terminal configured to output a detection signal corresponding to a radio frequency signal that is transmitted through the main line, the first sub-line and the second sub-line are different in length from each other, and connection between the first sub-line and the coupling terminal and connection between the second sub-line and the coupling terminal are switched.