To provide a twist vibration attenuation mechanism of a differential device which can effectively attenuate twist vibration in an input mechanism portion of the differential device without complicating the structure of a differential case.

A twist vibration attenuation mechanism 60 is constituted by arranging a friction member 62 at the end face of one drive shaft 41, a plate member 63 sliding with respect to the friction member 62 at the end face of the other drive shaft 38, and an elastic member 64 for push-pressing the plate member 63 to the friction member 62.