Nanocomposite TiO2/WO3/Bi2WO6 photocatalysts were firstly prepared from anatase TiO2 nanoparticle-doped WO3/Bi2WO6 nanosheets, which were synthesized via hydrothermal reaction of sodium tungstate dihydrate and bismuth nitrate pentahydrate at optimized temperature, and then went through surface modification by a high density tubular plasma discharge device. The samples were characterized and analyzed by XRD, SEM, TEM, HRTEM, XPS, UV-Vis DRS and PL followed by investigation of their photocatalytic performance on methylene blue (MB) degradation in water under visible light irradiation. The results showed the the optimal hydrothermal reaction temperature was 120 ℃, at which WO3/Bi2WO6 nanosheets synthesized displayed better photocatalytic performance. Moreover, The TiO2/WO3/Bi2WO6 nanocomposites doped with 10.7 wt% anatase TiO2 nanoparticles exhibited significant photocatalytic activity enhancement in comparision to WO3/Bi2WO6 nanosheets. More importantly, the tubular plasma discharge surface modification made the absorption edge of the TiO2/WO3/Bi2WO6 nanocomposites redshift at visible light, and the increase of discharge input power helped improve the photocatalytic activity of the nanocomposite. At peak discharge voltage of 1.1 kV, the degradation rate constant of the composite was 2.2-fold and 3.9-fold those of TiO2/WO3/Bi2WO6 without surface modification and WO3/Bi2WO6 nanocomposites, respectively.