To provide an acoustic wave branching filter whose filter characteristic is excellent and whose level of mutual modulation distortion is low.

A reception filter 20 includes first and second longitudinal coupling resonator type surface acoustic wave filter parts 30a and 30b and a surface acoustic wave resonator 40. The first and second longitudinal coupling resonator type surface acoustic wave filter parts 30a and 30b each include at least three IDT electrodes 31 to 33. The surface acoustic wave resonator 40 includes an IDT electrode 41 connected to at least one of at least three IDT electrodes 31 to 33. The reception filter 20 is constructed so that a ratio (C1/C2) between a capacity C1 of the surface acoustic wave resonator 40 and a capacity C2 of the IDT electrode 31 electrically connected to the IDT electrode 41 falls within a range of 1.9 to 2.5 inclusive.