Objective:To study the effects of 1?,25-dihydroxyvitamin D 3 and UVB on cell proliferation and melanin synthesis of normal human melanocytes. Methods:Melanocytes of foreskins of healthy men were cultured and treated with various concentration of 1?,25-dihydroxyvitamin D 3 or UVB (55 mJ/cm 2),or both.Cell proliferation was measured with MTT assay .The synthesis of melanin was determined by chromatography. Results: 1?,25-dihydroxyvitamin D 3 and UVB could promote the proliferation of cultured melanocyte,and 1?,25-dihydroxyvitamin D 3 could promote the melanin synthesis.The significant concentration of 1?,25-dihydroxyvitamin D 3 ranging from 10 -7 to 10 -10 mol/L.Conclusion:1?,25-dihydroxyvitamin D 3 and UVB irradiation could promote the proliferation of melanocyte,which indicates that they might be effective in the treatment of vitiligo.