Although laser cladding coatings have been extensively employed in mechanical components, challenges such as excessive dilution, high porosity, and insufficient in-situ synthesized ceramic phases still exist. To mitigate these problems, U-groove-assisted laser cladding Ni-based composite coatings were fabricated in this study. Regression models were established by response surface methodology to analyze the combined influence of U-groove depth and process parameters on the dilution rate, porosity, and microhardness of the coating, enabling multi-objective optimization. The optimal combination of parameters was determined to be a U-groove depth of 0.4 mm, laser power of 450 W, scanning speed of 5.3 mm/s, and powder feeding rate of 1.3 r/min, with a maximum prediction error within 10 %. The microstructure evolution, microhardness, wear behavior, and corrosion resistance were systematically studied. Compared with the coating without grooves (Flat), the introduction of 0.4 mm U-shaped grooves (G04) prolonged the thermal holding time of the molten pool and enhanced melt flow efficiency, thereby promoting the in-situ synthesis of ceramic phases. Consequently, the microhardness of G04 increased by 14.3 %, and its wear rate decreased by 88.9 % compared with Flat. Additionally, the corrosion current density of G04 was reduced by 78.6 %, which is attributed to the lower porosity and the barrier effect of uniformly distributed TiC particles. This research provides technical guidance for improving the performance of laser cladding coatings.