A drive transmission device includes: a gear, provided with a shaft hole, for transmitting a driving force; a frame to which a fixing shaft for rotatably supporting the gear by engaging with the shaft hole is fixed, wherein during transmission of the driving force, the gear is urged in a radial direction of the shaft hole, and a predetermined region of an outer peripheral surface of the fixing shaft slides on an inner peripheral surface of the shaft hole; and a holding portion, provided in a position closer to a center of the fixing shaft than the predetermined region with respect to a radial direction of the fixing shaft, for holding a lubricant between itself and the shaft hole. The holding portion is disposed only in a position opposite the predetermined region with respect to the center of the fixing shaft.