Lithium storage materials with porous and sheet-like structure are featured with favorable electrode/electrolyte accessibility and a shortened lithium diffusion distance, which can possess a fast electron and ion transportation. Here, a synchronous carbonization and phosphorization method was developed to synthesize flower-like CoP/C nanosheets by using Co-based metal organic complex as a precursor. The flower-like CoP/C nanosheets electrode exhibits a high initial Coulombic efficiency and excellent specific capacity. A reversible capacity of 612 mAh g−1 is obtained at a current density of 400 mA g−1 after 500 cycles. When used as a hydrogen evolution reaction electrocatalyst in acidic media, the unique flower-like CoP/C nanosheets perform an onset over potential of 151 mV and a Tafel slope of 128 mV dec−1. As a consequence, the flower-like CoP/C nanosheets are a promising material for lithium ion batteries and hydrogen evolution reaction.