In this study, methyl mercaptan (CH3SH) gas was used to prepare synthetic odorous gases, and a photocatalytic wet scrubbing process as a new approach was developed for treating such odorous gases. In this process, gaseous CH3SH is first absorbed by the solution, and the dissolved CH3SH/CH3S- is then adsorbed onto the solid surface of TiO2 particles and oxidized under UV illumination in the aqueous phase. Experiments were conducted under different reaction conditions of CH3SH loading, TiO2 dosage, and pH. The reaction kinetics of CH3SH reduction indicates that the pH of the reaction solution greatly influences the rate of CH3SH absorption by the solution. At pH < 11.5, CH3SH absorption by the solution is the rate-determining step (RDS), whereas at pH > 11.5, the photoreaction becomes the RIDS in such a system. The experiments demonstrated that the efficiency of CH3SH degradation determined by two methyl mercaptan sensors and the ratio of odor removal determined by olfactometry measurements can be well maintained at high levels of >95% for a CH3SH loading of 10 g m(-3) h(-1). The main intermediates and final products from CH3SH degradation were identified by GC/MS and ion chromatography, and a pathway for CH3SH degradation with three routes is proposed and discussed. Odor samples to simulate real foul gases were also prepared and treated with this new process. An electronic nose technique was applied to indentify the patterns of odor characteristics before and after treatment.