Based on laser coaxial powder feeding deposition technology, the forming control of 316 L stainless steel additive manufacturing components was studied. The influence of printing plane position on joint size and layer height on joint size is analyzed, and regression relationship model between joint size and process parameters is established. The results show that when the printing plane is on the plane where the laser focus is, the fluctuation of the printing plane with the actual layer height will occur an automatic feedback adjustment process; the actual layer height will be automatically adjusted with the set layer height until the actual layer height and the set layer height are basically consistent, and there is an optimal layer height setting value under different powder deposition rates; the return between joint size and process parameters is obtained. The single wall and solid additive components with good shape were prepared by optimizing the process.