The processing parameters have an important influence on the performance of the parts during the selective laser melting (SLM) process. Therefore, in this study, the influence of different scanning speeds and laser powers on the performance of the Ti6Al4V alloy parts fabricated by selective laser melting have been investigated, mainly including the fracture behavior of the parts. The fracture mechanism of Ti6Al4V alloy parts fabricated by selective laser melting has been also studied by investigating their microstructures. The experimental results show that: The fracture morphologies of the Ti6Al4V alloy parts under different processing parameters are significantly different. The size of grains at the fracture and internal pores defects of the Ti6Al4V alloy parts can be effectively adjusted by selecting different scanning speeds and laser powers. Through the analysis of the fracture morphology of Ti6Al4V alloy parts, the optimized processing parameters are obtained: laser power of 240 W, scanning speed of 1 200 mm/s, powder layer thickness of 0.03 mm and hatch spacing of 0.14 mm. At this time, the tensile strength of Ti6Al4V alloy parts can reach 1 179 MPa.