Abstract: Aiming at the welding difficulties faced by the stainless steel carbody sidewall of Thailand railway passenger train, the welding tong structure process parameters of resistance spot welding equipment is studied, and the overall process flow of sidewall manufacturing is reorganized. The process and technical requirements of small frame welding of segmented sidewall, large frame welding of integral sidewall, wallboard welding, manual window cutting process and resistance spot welding chemical blackening removal process are described in detail. By designing interchangeable resistance spot welding equipment with large and small throat deep welding tongs, adopting reverse welding frame, front welding wallboard and other technologies and reasonably determining welding parameters, the manufacturing of railway passenger train sidewall with all resistance spot welding processes can be realized.