Abstract: The combination of photocatalyst and building materials is an emerging direction of development in the photocatalytic field. In this paper, the photocatalytic activity of nano-TiO₂ cement is measured by the degradation efficiency of methyl orange. The influence of the dose of photocatalyst, differentTiO₂ contents, curing age and the initial concentration of methyl orange on the degradation efficiency ofmethyl orange are investigated. Experimental results indicate that the optimum photocatalytic efficiencywould be achieved under the following conditions: initial concentration of methyl orange at 5 mg/L, photocatalyst dose at 3 g/L, and cement with 5 % TiO₂. The adsorption performance and degradation efficiency ofphotocatalytic cement would decrease with the prolonging of curing age. The adsorption property of photocatalytic cement is enhanced with the increase of initial methyl orange concentration. The adsorption efficiency of photocatalytic cement is up to 54.5 % when the initial concentration is 15 mg/L.