Abstract: Combining with the chemical composition of the base material, welding material and welding parameters control, through the micro organization, phase ratio, mechanical properties, and corrosion performance of Cr25 series casting super duplex stainless steel 5A（UNS J93404） welding joint, the result shows that in order to control the proportion of the parent material, obtain excellent welding joint, not only need to control the Si content of the base material, choose the matching welding material, but also strictly control the heatinput of the welding process.