To provide a drive transmission mechanism, in which drive transmission delay is not generated between a drive transmission part of a drive rotary body and a driven rotary body, and in which vibration and noise can be reduced in accordance with characteristics of an elastic member.

The drive rotary body 20 is integrated with the drive transmission part as a rod-shaped projection 21, and the driven rotary body 30 is integrated with a receiving part as a hollow projection 31. The drive rotary body 20 and the driven rotary body 30 are disposed to be coaxial with a rotary shaft 40, and the rod-like projection 21 is capable of getting in contact with an inner circumferential wall surface of the hollow projection 31 on one side. The elastic member 50 is provided to be capable of getting in contact with the inner circumferential wall surface of the hollow projection 31 on the other side of the rod-shaped projection 21. As the drive rotary body 20 rotates, the rod-shaped projection 21 is applied to the inner circumferential wall surface of the hollow projection 31 to push it, so that the driven rotary body 30 is rotated. Since the rod-shaped projection 21 directly rotates the driven rotary body 30, drive transmission delay is not generated, and vibration and noise are reduced as effect of the elastic member 50.