Provided is a speaker device in which reproduction sound pressure is increased, and heat resistance and water resistance are improved. The speaker device includes: a diaphragm formed of a film containing polyimide; and a frame for supporting the diaphragm. A cross-section passing the center of the diaphragm and parallel to a sound emission direction includes sequentially from an inner periphery to an outer periphery of the diaphragm along the sound emission direction: a first bent plate portion having a concave arc; a second bent plate portion having a convex arc; a third bent plate portion having a concave arc; and a fourth bent plate portion having a convex arc. An area of the first bent plate portion is larger than any of areas of the second, the third, the fourth bent plate portions.