The invention discloses an automatic soldering tin machine for a terminal pin of a transformer. The automatic soldering tin machine for the terminal pin of the transformer comprises a machine frame, a transverse movement device, a lifting device, a clamping device, a soldering tin device and a feeding device. The transverse movement device comprises guide rails, a sliding block is arranged on the guide rails, the sliding block is connected with a transverse movement plate, the transverse movement plate is connected with a sliding sleeve, the sliding sleeve is connected with a transverse movement screw, and one end of the transverse movement screw is connected with a transverse movement motor. The lifting device comprises a lifting motor, the lifting motor is installed on a lifting frame, and the lifting frame is connected with the transverse movement plate through a guide rod; the output end of the lifting motor is connected with a lifting lead screw, and a lifting plate is arranged on the lifting lead screw. The clamping device comprises a support connected with the lifting plate, a transmission motor is arranged on the support, the output end of the transmission motor is in transmission connection with a clamping part through a belt, and the clamping part is hinged to the lower portion of the support. The soldering tin device comprises a scaling powder groove and a molten tin bath. The automatic soldering tin machine for the terminal pin of the transformer has the advantages of being simple in structure, reasonable in design, high in automation degree and stable in operation; in addition, the working efficiency is high, discharging is order, and the terminal pin of the transformer can be welded edge by edge.