Atmospheric-pressure dielectric barrier discharge (DBD) cold plasma was employed to fabricate Pt/TiO2 mesoporous photocatalyst. BET, XRD and TEM were used to characterize the Pt/TiO2 mesoporous photocatalyst. BET analysis showed that the mesoporous TiO2 has little change with the DBD plasma treatment. XRD spectra proved that H2PtCl6 was reduced to metallic Pt nanoparticles, and the Pt/TiO2 prepared by DBD plasma (Pt/TiO2-P) showed smaller Pt particles. TEM images showed that Pt particles were homogeneously distributed on the surface of Pt/TiO2-P, and the mean particle size of Pt was ca. 1.7 nm, which was much smaller than that in Pt/TiO2 prepared by thermal reduction (Pt/TiO2-C). Photocatalytic activity of the Pt/TiO2 mesoporous photocatalysts was evaluated by photodegradation of methylene blue (MB). Compared with the 0.5 wt% Pt/TiO2-C sample, 0.5 wt% Pt/TiO2-P exhibited a high activity for MB degradation, and the first-order rate constant in 0.5 wt% Pt/TiO2-P photocatalytic process was ca. 2 times higher than that of mesoporous TiO2. Atmospheric-pressure DBD cold plasma was proved to be a fast and facile method for preparing Pt/TiO2 mesoporous photocatalyst with enhanced activity. (C) 2013 Elsevier B.V. All rights reserved.