To obtain the recombination protein of renalase and prepare the monoclonal antibody, the human renalase gene was amplified from human kidney by specific primer and cloned the DNA fragments into the pET22b. After verification of the positive clones, the gene was transformed to E. coli BL21 to express the protein with 6His on C terminal. The Balb/c mouse was immunized with the purified protein to prepare the monoclonal antibody by hybidoma technique. The renalase protein was reconstructed and 2 strains of the hybidoma which can stable secrete renalase were obtained. The monoclonal antibody can both react with the both recombinant and human serum renalase.