S-doped TiO2 nanoparticles were fabricated by hydrothermal process and post-calcination, and their morphology, crystalline phase and chemical composition were characterized with transmission electron microscopy, powder X-ray diffraction and selected area electron diffraction. The results showed that S was successfully doped into the TiO2. We investigated the photocatalytic reactions in a simulated environment in tandem with thermal desorption-gas chromatography-mass spectrometry determinations. The catalytic activity of S-doped TiO2 was evaluated by monitoring the photodegradation of BTEX from wood-based panels, and 95% degradation rate in 75 min demonstrated efficient visible-light catalytic performance.