A loudspeaker diaphragm includes a diaphragm portion and an edge portion, which is molded integrally with the diaphragm portion and made of a material different from a material for the diaphragm portion. The edge portion contains at least one thermoplastic polymer (I), in combination with a block polymer (II). The at least one thermoplastic polymer (I) is selected from a block copolymer (I-a) which contains a polymer block (A) having a repeating structural unit derived from an aromatic vinyl compound and a polymer block (B) having a repeating structural unit derived from a conjugated diene, and an addition hydrogenated block copolymer (I-b) of the block copolymer (I-a). The block copolymer (II) contains a polymer block (C) having a repeating structural unit derived from an olefin compound and a polymer block (D) having a repeating structural unit derived from a (meth)acrylic compound.