A Co-MOF, [Co-3(HL)(2)center dot 4DMF center dot 4H(2)O] was simply synthesized through a one-pot solvothermal method. With the semiconductor nature, its band gap was determined to be 2.9S eV by the Kubelka-Munk method. It is the first trinuclear Co-MOF employed for photocatalytic hydrogen evolution and CO2 reduction with cobalt-oxygen clusters as catalytic nodes. Hydrogen evolution experiments indicated the activity was related to the photosensitizer, TEOA, solvents, and size of catalyst. After optimization, the best activity of H-2 production was 1102 mu mol/(g h) when catalyst was ground and then soaked in photosensitizer solution before photoreaction. To display the integrated design of Co-MOF, we used no additional photosensitizer and cocatalyst in the CO2 reduction system. When -NH 2 was used for light absorption and a Co-O cluster was used as catalyst, Co-MOF exhibited an activity of 456.0 mu mol/(g h). The photocatalytic mechanisms for hydrogen evolution and CO2 reduction were also proposed.