The invention discloses an axial feed mechanism which comprises a screw drive unit, a connecting base, a ball screw, a splined shaft, a splined hub, a rotary sleeve, and a tool set. The splined shaft and splined hub are fitted together; the connecting base is fixedly mounted to the upper portion of the splined hub; upper end of the ball screw is driven by the screw drive unit mounted to the connecting base; lower end of the ball screw goes downwards through the connecting base and connects with the upper end of the splined shaft, and the ball screw and connecting base are locked closely axially; the rotary sleeve is longer than the splined hub, and is fixed outside the splined hub in rotatable sleeve mode along the axial and radial directions; the tool set is mounted to the lower end of the rotary sleeve; lower end of the splined hub is provided with a positioning device which extends into the pipe for positioning. With less space occupation, convenience in operation, and high accuracy of feeding, the axial feed mechanism is applicable to narrow work space and fixation of pipes.