An electronic device comprises a housing including a window member facing a first direction, a rear housing facing a second direction that is opposite to the first direction, and a side member encompassing the space between the window member and the rear housing. The electronic device also includes a display that is visible through at least a part of the window member and a speaker assembly disposed in the space. The speaker assemble includes a speaker diaphragm. The side member includes a resonance space including a shape a recessed form in a third direction that is substantially perpendicular to the first direction or the second direction. A through hole is formed in the third direction in a part of the resonance space that is closer to the rear housing than to the window member. A part of the resonance space can be disposed so as to overlap the speaker diaphragm.