The invention discloses a transmission connecting structure and method. The transmission connecting structure comprises a worm and a guide pipe. The worm and the guide pipe are connected through a connecting assembly composed of a nut and a metal insert. The nut and the metal insert are formed through integral injection molding. One end of the connecting assembly is connected to the worm, and the end provided with the metal insert is buckled and embedded in the guide pipe. According to the transmission connecting structure and method, the structure is simple, producing and machining are convenient, installing and connecting are rapid and convenient, reliable connection from motor output force to a tail door system can be ensured, durability and reliability of a supporting rod system are effectively guaranteed, the product design requirement is met, and good application prospects are achieved.