A differential case includes a first boss part into which a first drive shaft is inserted, and a second boss part into which a second drive shaft opposed to the first drive shaft is inserted. The differential case is composed of: a first case body extending from pinion-shaft assembling parts on which a pinion shaft is assembled, to a ring gear; a second case body having the first boss part; and a third case body having the third boss part. The first case body is integrally formed by forging. The second case body is integrally formed by forging. The third case body is integrally formed by forging. The first case body and the second case body are joined to each other by welding. The first case body and the third case body are joined to each other by welding.