Mn-N duplex stainless steel surfacing samples were prepared by powder surfacing and solution heat treatment.The metallographic structure of the surfacing layer was observed.The corrosion resistance of the surfacing layer was studied by the ferric chloride immersion experiment and the polarization curve method,and was compared with the surfacing layers of 2209 duplex stainless steel and 304 austenitic stainless steel respectively. The results show that the metallographic structure of the self-made Mn-N duplex stainless steel surfacing layer is austenite and ferrite,and the two-phase ratio is close to 1:1. The presence of ferrite provides sufficient Cr for the grain boundary and reduces the carbon precipitation of Cr,and the pitting resistance is better than 304 austenitic stainless steel;the corrosion resistance of Mn-N duplex stainless steel is slightly worse than that of 2209 duplex stainless steel,the reason is that its chromium and molybdenum are lower than those of 2209 duplex stainless steel,which reduces the stability and repassivation ability of the passivation film.