The invention relates to a tube cutter, which comprises cutting element, transmitter, guide blade rod and feeding steel wire, wherein the cutting element is at the head of guide blade rod; the transmitter is at the end; the cutting element is mounted on the square hole at the head of blade rod; the return spring blade is inserted into the hole of blade via screw to be fixed at the guide blade rod; the transmitter via adjusting sheath is fixed on the guide blade rod; the rotation sheath is on the blade rod; the rotation handle is connected to the rotation sheath via screw; the feeding nut is connected to the tail of guide blade rod via screw; one end of feeding steel wire is connected to the feeding taper via screw; via rotating the feeding nut, the steel wire will move taper downwards to expand the cutting. The invention can reduce pollution, reduce cost and improve efficiency.