The plane-wave ultrasoft pesudopotentials based on the density functional theory is used to study the formation energy, the electronic structure and the optical properties of molybdenum and different nonmetallic elements codoped anatase TiO2, where the nonmetallic elements are boron, carbon, nitrogen, oxygen and fluorine. Firstly, we calculate the total densities of states and the band structures of different kinds of codoping TiO2, and analyse the codoping modulation effect on band gap by using the energy band theory. Furthermore, we analyse the synergistic effects on stability and catalysis of TiO2 caused by codoping. And then the state of each atom's bond effect is obtained by analysing the total density map. Finally, we come to the conclusion that molybdenum-carbon codoping structure is superior to others on modulating the photocatalysis of TiO2 in visible light. Our theoretical research will be instructive and meaningful for photocatalysis area of TiO2 in the future.