The hsDC2, an unknown gene, was located on chromosome 4q25. The genetic protein product contained 149 amino acids with the molecular weight of 16.8 kDa. By bioinformatics, three predicted non-membrane portion of hsDC2 gene were designed to immune rabbit. The hsDC2 a1~31and hsDC2 a54~82 gene were inserted in pGEX6p-1 that expressed as fusion protein with GST. The other, hsDC2 a140~149, was synthesized with additional cycteine for conjugation with mcKLH at N-terminal. After four times subcutaneous injection, the antiserum was blooded from rabbits. The antibody was purified from the antiserum by protein A beads and confirmed with antigen by western blotting. The identified antibody was used to examine the expression of hsDC2 protein during U937 differentiation induced by RA and PMA.