PURPOSE: To obtain a speaker diaphragm with an edge suitable to a diaphragm body high in specific elastic modulus at its cone surface and small in internal loss.

CONSTITUTION: Diaphragm body 13 is a conic diaphragm body high in specific elastic modulus E/ρ and low in internal loss tanδ such as aluminium foil and titanium foil, and to its circumferential part, free edge 14 is stuck which consists of material 15 such as carbon fiber high in specific elastic modulus and material 16 such as urethane resin large in internal loss. As a result, main body 13 and edge 14 keep balance in terms of modulus of elasticity and reverse resonance can be prevented from occurring to the edge in an in-use band, so that the reproduction band can be widened without deteriorating sound-pressure frequency characteristics and distortion characteristics.