Abstract: In order to find out the causes of welding cracks in the process of welding 304 H and 310 S steels, the weldabilities of 304 H and 310 S were studied respectively, and the weldability between 304 H and 310 S were studied, including the choosing of welding materials, welding method, welding procedure, properties and metallographic structure of welded joints. The welding procedure that was appliable and could be used to guide the production was obtained.