The W-25Re alloy was prepared by selective laser melting (SLM) using spherical W-25Re (mass fraction, %, hereinafter) alloy powder as the raw material. The effects of process parameters on the relative density, microstructure and micro-Vickers hardness of W-25Re alloy were investigated. The relative density, microstructure, phase composition, and micro-Vickers hardness of W-25Re alloy were characterized by analytical balance, field emission scanning electron microscope (FE-SEM), X-ray diffractometer (XRD), microhardness tester. The results show that there are no obvious spheroidization, warping, deformation, delamination or non-forming phenomena during the preparation of W-25Re alloy by SLM. There are no obvious defects such as holes and cracks on the surface and side of the specimens, and W-25Re alloy formability is good. With the increase of E_v, the grain morphology in the vertical plane of W-25Re alloy specimens gradually changes from the mixture of equiaxed and columnar grains to coarse columnar grains. W-25Re alloy specimens only contain the cubic W13Re7 phase, and the change in the leftward shift of the diffraction peak 2θ angle is mainly caused by residual stress during the forming process. The influence of laser power and scanning speed on the relative densityof W-25Re alloy is significant. When E_v is 1050 J/mm₃^{, that is, the laser power is 210} W and the scanning speed is 200 mm/s, the W-25Re alloy specimen with a relative density of up to 98.49% can be obtained. At this time, the microhardness of the specimen in the horizontal and the vertical plane is as high as 525.9 HV0.2 and 520.6 HV0.2, respectively, which is close to the hardness value of the rolled W-25Re alloy.