The invention discloses an automatic doffing device comprising a doffing dolly, wherein the outer side of the side wall of the doffing dolly is fixedly connected with two truckle fixing plates and a photo-sensor, two truckle fixing plates are respectively provided with a first truckle and a second truckle fixedly connected to an elastic slide block; a servo motor connected with a gear is installed in the doffing dolly; the gear is meshed with a rack and can move along the rack; the rack is fixedly connected to the lower end surface of a first rail; the first rail is fixedly connected with a main rail support frame provided with a localizer; the main rail support frame is fixedly connected with a second rail; the first truckle and the second truckle are respectively positioned on the first rail and the second rail to be connected; the top of the doffing dolly is provided with a three-dimensional robot respectively connected with a control system and a detection system; and the three-dimensional robot is connected with a non-synchronous tube drawing mechanism and is provided with a limit switch. The automatic doffing device of the invention instantly pulls small amounts of spools, reduces yarn pulling peak force, has convenient installation, precise positioning and stable doffing and is easy to realize standardization.