A vacuum activated approach is employed to prepare fluorine doped TiO2/mesocellular foams (F-TiO2/MCF) by using ammonium fluoride (NH4F) as a fluorine source. In this work, MCF were used as the supporter for TiO2 particles loading owing to its thermal stability and suitable pore size. Furthermore, NH4F is easier to afford as compared to traditional organic fluorine reagents. As expected, F-TiO2/MCF demonstrates high photocatalytic activity and stability on pollutant degradation and hydrogen evolution. Under solar light irradiation, the degradation rate of methyl orange (MO) can be up to 93% within 7 min. The outstanding photocatalytic performance of F-TiO2/MCF is ascribed to abundant F atoms filling into oxygen vacancies in TiO2 and high specific surface area. The vast F atoms doping TiO2 lattice are favorable to eliminate defects-induced recombination sites and ensure the excellent photocatalytic activity.