Abstract: Laser welding with hot wire addition can precisely control the heat input and therefore it can efficiently clad the metal, which is suitable for surface repairing. There are few reports on the analysis and optimization of weld formation quality of laser hot wire multi-pass repair welding. Based on RSM (response surface methodology), laser power, scanning speed, wire feed rate and overlap ratio were selected as process variables, while surface flatness, dilution rate and incomplete fusion ratio as response parameters. The results indicated that the surface flatness, the dilution rate and the incomplete fusion ratio had a quadratic relation with these variables. Meanwhile, an optimal cladding layer with no incomplete fusion, low dilution rate and good surface flatness was obtained by appropriately reducing the wire feed rate, and increasing the laser power, the scanning speed and the overlap ratio. By using overlap contour, multiple responses were comprehensively optimized according to the specific requirement of formation quality.