To evaluate the elevated-temperature service performance of aero-engine components of GH3536 alloy formed via selective laser melting (SLM), tensile specimens were manufactured via SLM with optimized parameters and were treated using stress relieving and hot isostatic pressuring (HT+HIP). The tensile properties of the specimens were tested at 20--815 ℃ and the microstructures, fracture morphology, and fracture mechanism were analyzed. The results show that after HT+HIP treatment, (Cr,Mo)23C6 precipitates at the grain boundaries, a columnar-to-equiaxed transition partially occurs, however, the directional solidification characteristic is still present. There are finer grains and more grain boundaries on the transverse section. Fracture analysis shows chains of precipitated carbides along the grain boundaries weaken the grain boundaries; in addition, intergranular fracture was observed. Owing to the anisotropy of the grain size, the mechanical properties and fracture morphologies vary with the specimen building direction. As the temperature increases, the tensile strength decreases and the elongation first increases and then decreases. The tensile failure mechanism changes as the temperature increases; this is characterized by stronger trend of intergranular fracture, smaller plastic deformation, and longer cracks at elevated temperature.