The loudspeaker includes a dome diaphragm that is made of a base material impregnated in a thermosetting resin; a cone diaphragm whose outer circumference side end portion is coupled with an outer circumference end portion of the dome diaphragm; and a voice coil having a bobbin whose one end is coupled to a back surface of the dome diaphragm, and whose outer curved surface is coupled with an inner circumference end portion of the cone diaphragm, wherein the dome diaphragm is provided with a plurality of cone-shaped projections that is formed by hardening the thermosetting resin, projecting from the back surface, and disposed in a circular pattern with a space between each other, the plurality of cone-shaped projections defining a coupling portion to which the one end of the bobbin is coupled.