The current forming quality and mechanical properties of the additively manufactured Inconel 718 alloy are difficult to control. Inconel 718 deposition layer was fabricated on the surface of H11 steel via the technology of laser directed energy deposition to investigate the effect of process parameters on the characteristics and microhardness of the deposition layer. The effects of laser power, scanning speed and powder feeding rate on the geometrical morphology, aspect ratio, dilution rate and microhardness of deposition layer were studied by means of orthogonal experimental. The process parameters were optimized with the aim of aspect ratio, dilution rate and microhardness. The final optimized process parameters were laser power 1 800 W, scanning speed 10 mm/s, powder feeding rate 19.71 g/min. Better quality deposition layer can be obtained by applying optimized process parameters.