Process parameters in the selective laser melting (SLM) process are crucial for determining the quality and accuracy of as-formed parts, making their optimization a key strategy for enhancing part formation quality and precision. This study designed single-track, single-layer, block build-up, and tensile experiments to improve the forming quality of TC4 alloy parts via SLM by optimizing parameters such as scanning speed, laser power, and scanning space. In the single-track experiment, the effects of scanning speed and laser power on the width of the cladding bead were obtained. Then, five sets of matching parameters of laser power and scanning speed were selected for single-layer experiment by observing the continuity of the cladding bead morphology and measuring the uniformity of the cladding bead width. In the single-layer experiment, the influences of scanning space on surface roughness and surface morphology quality were analyzed. Subsequently, ten sets of process parameters were chosen for block build-up experiment in terms of the surface quality and surface roughness of the cladding layer. In the block build-up experiment, the effects of linear energy density and scanning spacing on the relative density were investigated. In accordance with the relative density of as-formed blocks, three sets of process parameters were selected for tensile experiment. Finally, on the basis of the tensile strength and elongation, the optimal combination of process parameters was selected as follows: laser power 200 W, scanning speed 1.0 m/s, scanning space 80 μm.