In this paper, the biocompatibility of plasma sprayed Al2O3, ZrO2, hydroxyapatite and wollastonite coatings were discussed. Osteoblasts isolated from neonatal rat calvaria were cultured onto the surface of coatings. Scanning electron microscopy was used to observe the variations of cell morphologies to reflect the biocompatibility of the coatings. Osteoblasts were difficult to grow and proliferate on the surface of alumina coating, indicating plasma sprayed Al2O3 coating possesses poor biocompatibility. The osteoblasts can grow and proliferate on the surface of ZrO2 coating. However, the growing and proliferating rate of osteoblasts oil. the surface of ZrO2 coating is lower than that on the surface of bioactive ceramic coatings, including HA coating and wollastonite coatings. Therefore, the biocompatibility of bioactive ceramic coatings is better than that of bioinert ceramic coatings.