Macroporous TiO2 nanocrystalline (NC) membranes with average pore size of 0.35 mu m were successfully fabricated by coating on an alumina support via a rapid atmospheric plasma spraying CAPS) approach. The as-prepared TiO2 and P25 membranes were first tested for photocatalytic activity using Reactive Black-5 (RB5) dye in a batch reactor with UV light irradiation, respectively. RB5 dyes were completely decomposed with an irradiation time of 70 min, and the rate constants for the photocatalytic reactions using TiO2 and P25 membranes were determined to be approximately 0.076 and 0.071 min(-1), respectively. The photocatalytic activity of the as-prepared TiO2 NC membranes was slightly better than P25 membranes, indicating the APS-fabricated TiO2 NC membranes were with a high photocatalytic activity. The TiO2 membranes were further used for the photodegradation of dextran and humic acid (HA), and the permeate fluxes of dextran and HA increased when the membranes were exposed to UV light irradiation. The dominant filtration resistances of the dextran and HA solutions were pore and cake resistances, respectively, which were reduced by a photocatalytic TiO2 NC membrane under UV light illumination. The removal percentages of HA at an initial concentration of 2 ppm were 58% and 90% in the dark and under UV light irradiation, respectively. The increase in the HA removal resulted from the photodegradation of HA by the photocatalytic TiO2 NC membrane. In this work, a rapid process of APS coating was first used for the preparation of macroporous TiO2 NC membranes with high photocatalytic activities, which can be applied for water treatment, for example, in the photodegradation of bio-organisms and protein under UV light irradiation. (C) 2011 Elsevier B.V. All rights reserved.