The invention provides a method of in-situ synthesis of a porous nano Co3O4/C anode material and belongs to the field of electrochemical. The method particularly includes steps of: synthesizing a rod-like porous cobalt-based metal organic framework through a solvothermal method, and washing, soaking and vacuum-drying a product to obtain a precursor; performing high-temperature carbonization decomposition to the precursor in a tubular furnace with an inert gas/oxygen mixture atmosphere, thus preparing a hierarchical porous nano/micro rod-like Co3O4/C anode material. In the invention, with the porous and large-specific-surface-area cobalt-based metal organic framework, which has periodical network crystal structure, being a self-template precursor, the hierarchical porous nano/micro rod-likeCo3O4/C anode material is prepared through the in-situ th ermal decomposition. The method has simple process. The anode material has high conductivity and specific capacity, and is excellent in cyclic stability.