A fixing device includes a fixing member that is rotated by a driving unit and that fixes a developer image on a recording medium; an external heating member that is driven and rotated while contacting an outer peripheral surface of the fixing member, and that heats the fixing member; a moving unit that moves the external heating member between a separation position and a contact position, and that moves the external heating member from the separation position to the contact position after starting the fixing by the fixing member; a drive transmitting mechanism including a fixing-side gear, an external-heating-member-side gear, and a drive transmitting member; and a driving force transmitting/non-transmitting unit that is provided at the drive transmitting mechanism.