Stomach tube convenient to replace

The stomach tube convenient to replace comprises a stomach tube body, a metal guide wire is arranged on the inner side wall of the stomach tube body in a penetrating and inserting mode, one end of the metal guide wire is fixedly connected with a metal ball, and the other end of the metal guide wire is sleeved with a positioning ring in a sliding mode. A fastening mechanism used for limiting the metal guide wire is arranged on the outer side wall of the positioning ring in a penetrating mode. According to the stomach tube, the stomach tube body, the metal guide wire, the positioning ring, the threaded rod, the positioning plate and the adjusting disc are matched with one another, the metal guide wire can be sleeved with the positioning ring during adjustment, the positioning plate abuts against the metal guide wire by rotating the threaded rod, in this way, the limiting effect can be achieved, and the position of the metal guide wire can be marked after the stomach tube body is moved out; the metal guide wire