Abstract: A golf swing training device for teaching a golfer the proper swing plane, including an elongated shaft member which is positioned in the ground next to the golfer during the execution of a golf swing, and an obstruction which is adjustable along the longitudinal axis of the shaft. The obstruction interferes with the club as it is swung in the backswing and deflects the club upwardly to the proper position at the top of the backswing. The downswing is made inside the elongated shaft to ensure a proper inside-out swing plane.