This research investigated the influence of different processing parameters in curved surface multi-track laser cladding with curve paths. Mathematical models of flatness ratio, incomplete fusion, and pore area in the clad were developed by central composite design with altering the input laser power, scanning speed, gas flow, and overlapping rate. Response surface methodology was used to analyze the correlation of different processing parameters affecting the selected responses. A clad with better flatness ratio was achieved by properly increasing the laser power and gas flow while reducing the overlapping rate. Appropriately increasing the laser power and overlapping rate while reducing the scanning speed and gas flow effectively diminished the incomplete fusion. Less pore area in the clad was obtained by appropriately increasing the laser power and overlapping rate while reducing the scanning speed and gas flow. Afterwards, desired processing parameters set was obtained by the optimization with the target of maximizing the flatness ratio and also minimizing the incomplete fusion and pore area. Experimental validation with this processing parameter setup provided satisfactory clad, and the error rate for the flatness ratio, incomplete fusion, and pore area was 1.708%, 5.714%, and 6.522%, respectively. This paper provides the theoretical guidance for the prediction and control of the flatness ratio, incomplete fusion, and pore area in curved surface multi-track laser cladding with curve paths.