The TiO 2 photocatalyst doped with nitrogen was synthesized via a precipitation method and investigated in the oxidation of acetone vapor under UV (371 nm)and visible light (450 nm). The data were collected in a continuous-flow set-up equipped with a long-path IR gas cell for in situ analysis of oxidation products and evaluation of the photocatalytic activity. The IR spectra for inlet and outlet reaction mixtures and their change during the process are presented. A technique for quantitative analysis of initial substrate and oxidation product using collected IR spectra is described. The effects of main operational parameters, namely, outlet concentration of oxidizing substrate in the range of 0–25 μmol/L, humidity in the range of 10–85%, and surface density of photocatalyst in the range of 0.6–5.7 mg/cm 2 were investigated, and the data received are presented. The data show the influence of these parameters on the UV and visible light photocatalytic activity of N-doped TiO 2 . The data is publicly available on GitHub according to the link: https://github.com/1kovalevskiy/Effect-of-the-operational-parameters.