A drive transmission device, which is included in an image forming apparatus, includes a first drive transmitter having a first hollow body, a second drive transmitter having a second hollow body, a link device, and a releasing device. The link device links the first and second drive transmitters and includes a first inserting body with a projection, a second inserting body with a projection, and a link body. The first and second drive transmitters have respective grooves in the first and second hollow body in an axial direction. The second drive transmitter is disposed at an end portion of a shaft of a rotary body detachably attached to a housing of an image forming apparatus. The releasing device relatively moves the link device to the second drive transmitter in the axial direction and releases a link of the driving force between the rotary body and the image forming apparatus.