Abstract: Disclosed is a draw in-out apparatus that is suitable for an air circuit breaker having large capacity and size, the apparatus comprising: a movable plate meshed with the thread portion of a spindle so as to be movable back and forth; rack gear installed on the movable plate so as to be movable back and forth along with the movable plate moving back and forth; pinion gear installed to be meshed with the rack gear and rotatable according to the rack gear moving back and forth; a cam rotatable by a rotational driving force transferred from the pinion gear by being provided with a teeth portion meshed with the pinion gear and having a radius larger than those of the pinion gear so as to amplify a torque transferred from the pinion gear and provided with a cam slot portion for enduring a load of the main body and a reaction force generated when the main body and the cradle are electrically connected to each other while the main body is moved to a connected position; a pivot disposed on the cradle at a position ad