Using nano-TiO2 particles obtained by hydrolysis of titanium oxysulfate (TiOSO4) as the precursor, and polystyrene (PS) spheres as the template, TiO2 hollow spheres were successfully deposited on CPTi substrates through layer-by-layer self-assembly technology. After ultraviolet light (UV) irradiation, the TiO2 coatings were soaked in simulated body fluid (SBF) to explore their bioactivities. The effects of UV irradiation time and UV irradiation media on the bioactivities of nano TiO2 coatings were investigated. The results show that bone-like apatite can be formed on the surface of nano TiO2 coating irradiated by UV, and this reveals that the irradiated coating has good bioactivity. The amount of apatite formed on the surface of the coating increases with the increase of UV irradiation time. UV-irradiated media also influence the bioactivity of the coating. The bioactivities of nano TiO2 coatings irradiated in air and SBF are better than that in water.