Osteoblast differentiation of rabbit bone marrow cells on apatite-coated titanium by alkali-heat treatment was investigated in present paper. Titanium was subjected to alkali-heat treatment and soaked in acellular simulated body fluid to prepare surface apatite layer. Cell behavior and alkaline phosphatase activity and osteocalcin on apatite-coated titanium were compared with those on commercially pure titanium in vitro. The results show that initial cell adhesion on apatite-coated titanium is higher than that on pure titanium while cell growth rates at a late stage are not significantly different for both groups. Early and later osteoblast differentiation marks, alkaline phosphatase activity and osteocalcin, on apatite-coated titanium are higher than those on pure titanium. Apatite-coated titanium by alkali-heat treatment can increase osteoblast adhesion and displays a higher differentiation capacity for osteoblasts differentiation than that for commercially pure titanium.