We studied on the affect of adhesive cells on the corrosion resistance of implant metal. L929 fibroblastic cells, which were adhered on the surface of the metals, were cultured for 3 days. Then, the concentration of Ni ion dissolved to the cultured medium was measured with the ICP analyzer. About pure Ni, the amount of Ni ion concentration was increased with the cell density. For NiTi alloy, the amount of dissolution of Ni ion was slighter than that of pure Ni, but the correlation of the concentration between Ni ion and the cell density was significant. On the other hand, when the protein of the cell was fixed with 10% formaldehyde solution, the dissolved Ni ion concentration was slightly compared with that of the living cells. As the results, it was suggested that the corrosion resistance of implant metal was closely depended on the existence of the living adhesive cells.