The results of studies of the effects of the process for obtaining biocomposites containing alumina submicrocrystalline sintered corundum grains as a matrix and a bioglass CaO-SiO2-P2O5-Na2O system as a bound phase on its microstructure and biocompatibility are presented. Microscopic observation was carried out on samples (SEM), the real, an apparent, helium density, total porosity, surface area, SBET, volume and percentage of macro- and mesopores, the biocomposites surface roughness parameters (Ra, Rz, Rt, profile material ratio Rmr, linear bearing part, amplitude distribution of the ordinate) were determined. It has been found that with the increase in glass system content, the density of biocomposite is decreasing. Biocompatibility was determined by the degree of growth of a human skin fibroblast cell line CCL 110 cultured on these substrates for 96 and 360 hours. The best results for maintaining short-term (96 h) culture were obtained on the substrate without densification with 10 wt% admixture of a bioglass system.