In recent years, calcium titanate (CaTiO3) and carbon-containing materials have gained much attention in a number of biomedical material researches. To maximize the advantages of both materials, we developed a novel alkoxide method to get ‘‘calcium titanate with calcium carbonate’’ (CaTiO3–CaCO3). Thus, our previous result indicated that calcium carbonate could play a key role in the cell response of CaTiO3 material. In the present study we evaluated the effect of sintering time of CaTiO3–CaCO3 in osteoblastic response of KUSA/A1 cells. We examined the material characterization as well as cellular proliferation and mineralization of KUSA/A1 cells cultured with the materials. The results showed that Ca-TiO3–CaCO3 material sintered during 30 min, has better influ-ence on the bone marrow stromal cells for their proliferation and mineralization compared to CaTiO3-CaCO3 sintered at 2 and 10 h. These results suggest that sintering time could be directly related to the amount of carbon within CaCO3 being crucial in cell response. In conclusion, our preliminary find-ings indicate that CaTiO3–CaCO3 could play a more dominant and favorable effect on cell response when sintered for 30 minutes.