This study presents the effects of TiO on the photocatalytic performance of foam cement composites with porous structures. The higher porosity and more surface open pores in foam cement allows more UV light to deeply penetrate and activate the TiO inside the cement matrix so as to participate in the photocatalytic process. Foam cement with 0.3 wt.% TiO shows the best photodegradation performance of methyl blue (MB), which is 1.8 times higher than normal cement with 0.3 wt.% TiO and 1.2 times higher than normal cement with 3.0 wt.% TiO. It provides a more efficient way to use TiO in cement-based materials for eco-friendly buildings with improved photocatalytic performance.