Abstract: The welding process of the end to end joint is very important in the production of large-scale directly-driven permanent-magnet wind generator stator. Its lap length is one of the most important resistance brazing parameters and directly affect the electrical and mechanical properties of the joint. Simulation samples with Different lap length of 10 mm, 15 mm, 20 mm and 25 mm were made. By testing the electrical and mechanical properties, the effects of lap length of resistance brazed joint were analyzed. The rationality of the existing lap length of 20 mm was evaluated. For the joint with 20 mm length lap, the conductivity is a little better than that of base metal, the temperature rise performance is better than that of the base metal and meets the tensile requirements, and the macro metallographic testing was qualified.