The precursor was precipitated by hydrothermal method on the carbon cloth matrix, and the porous 3D CoP@CC material with arrays of nano-needle structure was prepared by heating the precursor in the atmosphere of Ar and sodium hypophosphiteat at 300-350 ℃. Its phase composition, microstructure and electrocatalytic performances were analyzed. XRD results indicate the sample is CoP with orthorhombic structure; SEM results indicate the diameter for the arrays of nano-needle structure is less than 100 nm and length is about 10 μm. The electrocatalytic performance results show that the 3D CoP@CC as catalytic materials exhibit excellent electrocatalytic hydrogen evolution reaction(HER) property in the 0.5 mol/L solution of H2SO4. The overpotential reaches 124 mV when the current density is 10 mA?cm-2. The slope of Tafel is 84.9 mV/dec, which indicates that the key reaction is Volmer reaction. There are two half circles of the EIS spectrum, which indicates that there should be two time constants. The value of 0.501 9 for CPE2-P indicates that double layer capacity should be produced on the roughly porous surface of the electrode, which is hard for carriers to transit; this also shows that the main resistivity is originating from mass transition and carrier transition.