The water absorption and photocatalytic activity of TiO 2 in a novel scrubber system for odor control using CH 3 SH gas as target compound was investigated. It was found that the amount of absorbed CH 3 SH in water increased with increasing initial pH of water, especially in basic water, which was approximately four times than those in acid and neutral water. Adding TiO 2 into water had little influence on the dissolved property of CH 3 SH in water with different pH. TiO 2 exhibited excellent photocatalytic activity in the scrubber system for CH 3 SH removal and reaction solution with high pH facilitated the photocatalytic degradation of CH 3 SH. In basic TiO 2 suspensions, 96.3% of dissolved CH 3 SH was degraded and the pseudo-first-order kinetic constant was roughly 1.5 and 2.7 times of those obtained in neutral and acid TiO 2 suspensions, respectively. Role of TiO 2 on CH 3 SH degradation in water was also discussed. Furthermore, the outlet concentrations of CH 3 SH all decreased to nearly zero after 60min of UV light irradiation in TiO 2 suspensions with different pH. Varieties in the pH of water and TiO 2 suspended solution after absorption and degradation process were measured. The absorption capacity of basic water with addition of TiO 2 was relatively stable and TiO 2 kept high photocatalytic activity for a long time (900min). This study provided helpful information on expanding the photocatalytic scrubber system for practical odor treatment.