This paper presents the results of research on o-cresol adsorption on both Cactive and TiO₂/C_active, and its photocatalytic oxidation on TiO₂/C_active. It was found that o-cresol adsorption on C_active was slow: equilibrium adsorption was reached after more than 20 hours. Adsorption isotherm fulfilled Langmuir equation: q_∞=1.153 mmole·g^-1, K=1,324 dm3⋅mole^-1. The adsorption was reversible. TiO₂/C_active as adsorbent behaved similarly to C_active itself, although the amount of o-cresol adsorbed per 1 g of TiO₂/C_active was about 10% smaller. It was concluded, based on the results of two-step experiments, that adsorption and photocatalysis (both the o-cresol dissolved in water and that partly desorbed from the surface of active carbon) was photooxidized when illumination of TiO₂/C_active followed 26-hour adsorption of the substrate on the photocatalyst-on-adsorbent. The loss of o-cresol dissolved in water fulfilled the 1^st order reaction kinetics. It was found in separate experiments that in the presence of illuminated titania, o-cresol molecules underwent hydroxylation preferentially in para position vs. original OH group. Hydroxylation of ortho position vs. original OH and of the CH₃ group was much slower.