The calcium sulfate (CaSO 4 ) bone scaffolds with high porosity and interconnectivity and controllable pore size were prepared by using selective laser sintering. The phase composition, micro morphology and biocompatibility were investigated by using X-ray diffraction, scanning electron microscopy and microculture tetrazolium test. The results showed that the CaSO 4 powders fused better and a more compact structure was built due to the decrease of holes in the scaffold at laser power of 7 W compared with 6 W or lower. At this time, both compressive strength and fracture toughness were optimal. While CaSO 4 decomposed and resulted in the mechanical properties decreasing when laser power further increased. Consequently, the mechanical properties of the scaffolds decreased. Moreover, the osteoblast-like cells attached on the scaffolds were obtained by cell culture in vitro. The results revealed that the cells could adhere and grow well on the scaffolds.