Abstract: Effects of laser processing parameters such as laser power,scanning velocity and powder feed rate on heat input coefficient(η) and shape coefficient of cladding layer(ζ) were investigated experimentally for TC4 Titanium alloy.The range of optimized processing parameters for laser rapid repairing of TC4 titanium alloy was determined in consideration of the requirements of laser rapid repairing on heat input coefficient and shape coefficient of cladding layer.With the optimized parameters,the deformation of laser rapid repaired parts was moderated and the repaired parts were well bonded.