A directional coupler includes: a main line connecting an input port and an output port; a first subline section and a second subline section each of which is formed of a line configured to be electromagnetically coupled to the main line; and a matching circuit provided between the first subline section and the second subline section. The matching circuit includes a first path connecting the first subline section and the second subline section, and a second path connecting the first path and the ground. The first path includes a first inductor. The second path includes a first capacitor and a second inductor connected in series.