A rotating device includes: an opening-closing portion supported so as to be openable and closable with respect to a support body; a drive unit provided on the support body; a first rotating body provided on the support body and rotated by a drive force of the drive unit; a driven portion provided in the opening-closing portion; a second rotating body provided in the opening-closing portion, rotated by a transmitted rotational force, and transmitting the rotational force to the driven portion; and an annular body formed in an annular shape, wound around the first rotating body and the second rotating body, maintaining the winding state in both an open state and a closed state of the opening-closing portion, and transmitting the rotational force of the first rotating body to the second rotating body.