The aim of this study was to investigate the influence of nanotubular surface on the behavior of MG-63 osteoblasts through determination of cell attachment, gene expression and calcium deposition. In this study titanium oxide nanotubes were prepared by anodization in 0.5 wt hydrofluoric acid solution for 60 min at 20 V. Osteoblast attachment was enhanced on anodized nanotubular surface compared to polished surface and micro-roughness surface. The expression level of bone associated genes(alkaline phosphatase (ALP), type I collagen) was detected by reverse transecriptase polymerase chain reaction (RT-PCR) After 9 days of culture, the expression of osteocalcin was highest on the nanotubular surface and not appeared on the polished surface. After 11 days of culture, the expression of osteocalcin was appeared only on the nanotubular surface. The result of this study showed the deposition of calcium and phosphate by osteoblasts cultured on anodized titanium with nanotubular surface after 11 days. In conclusion this study suggests that faster and better osseointegration might be attained on the anodized nanotubular surface.