The interface and quality of TiO_2 coated optical fiber,which is obtained by dipping nude fibers into TiO_2 slurry,were investigated. The coating processes were carried out under different designed conditions,including various adhesives,solid content of TiO_2 slurry,times of cladding and followed heat-treat temperature. The interface and coating qualities were observed by scanning electron microscope. Coating defects,such as cracking,breaking off and the inhomogeneity of the cladding corresponds to different coating condition were analyzed. As a result, a well-combined and durable TiO_2 coating in optical fiber surface was obtained under definite optimizing experimental conditions and parameters. The interface and quality of TiO 2 coated optical fiber, which was obtained by dipping nude fibers into TiO 2 slurry, were investigated. The coating processes were carried out under different designed conditions, including various adhesives, solid content of TiO 2 slurry, times of cladding and followed The interface and coating qualities were observed by scanning electron microscope. Coating defects, such as cracking, breaking off and the inhomogeneity of the cladding correspond to different coating conditions were analyzed. As a result, a well-combined and durable TiO_2 coating in optical fiber surface was obtained under definite optimizing experimental conditions and parameters.