The charge transfer and structural distortions that occurred in the complex CpRh(CO)2 upon excitation with an light irradiation were studied by density functional theory (DFT). The calculations showed that the electrons transferred from Cp to CO ligands with the transition of CpRh(CO)2 from ground state to the first excited state. Accompanying with this transfer process, CpM(CO)2 became distorted and the linear bond of M-CO became bent upon excitation. The second excitation is the strongest excitation which is identified to be metal to ligand CO charge transfer (MLCT) excitations. We also found the lowest excited state has little effect for the M-CO bond photoactivation while the photodissociation of CO from CpM(CO)2 can be achieved in the second excited state.