Abstract: In order to improve the wear and corrosion resistance of SUS 304 stainless steel, an alloyed layer of Cr-CrB2 was fabricated on SUS 304 stainless steel using laser surface alloying. The datum about microstructure, phases and the corrosion property of the alloyed layer were obtained. Dense and homogeneous structure and fine grains were observed in the alloyed layer. A metallurgical bonding interface was formed between the alloyed layer and the substrate. The alloyed layer consists of austenite, martensite, Fe-Cr, chromium carbide and chromium boride. The alloyed layer shows higher corrosion resistance and lower corrosion rate than the substrate. The polarization curve of the alloyed layer has a long activaton-passivation segment. Intergranular corrosion and pitting in the grains and the grain boundaries are observed for substrate, and intergranular corrosion occurs mainly in the boundary. The alloyed layer shows intergranular corrosion in combination with pitting in the grains and grain boundaries. The size of the pitting in the substrate is larger than that in the alloyed layer. The results have a great help on the improvement of the wear and corrosion resistance of SUS 304 stainless steel.