The invention discloses a supporting pipe. Inward-concave threads are formed on the inner wall of the supporting pipe, and the supporting pipe can be torn in the position of the inward-concave threads. The invention further provides an extrusion die for the supporting pipe. The extrusion die for the supporting pipe comprises a connecting cylinder, an inner die sleeve, a flow distribution cone, an outer die body, a rotary shaft and a hob. The flow distribution cone is arranged outside the inner die sleeve. The outer die body is arranged outside the flow distribution cone, and a molten material runner is formed between the outer die body and the flow distribution cone. The connecting cylinder is fixed to the flow distribution cone and the outer die body, and a cylinder cavity of the connecting cylinder communicates with the molten material runner. The rotary shaft which can rotate in the inner die sleeve is arranged in the inner die sleeve. The hob is arranged at the tail end of the rotary shaft, and the hob is located at an outlet of the molten material runner. The extrusion die can directly extrude the supporting pipe, and compared with the prior art that a supporting bar is produced firstly, and then the supporting bar is heated and spirally welded to form a supporting rod, the technique is simple, the production efficiency is high, and the production cost can be reduced.