OBJECTIVE： To study the effects of butin in Vernohia anthelmintica （VW） on proliferation of human immortal keratinocyte cell strain HaCaT and cell secretory factors， and explore the mechanism of butin in VW in the treatment of vitiligo. METHODS： MTT method was used to determine the survival rate of HaCaT cells cultured by 0 （blank control）， 0.1， 0.5， 1.0， 5.0， 10.0 μg/mL of butin for 48 h. Enzyme-linked immunosorbent assay was used to determine the contents of cell secretory factors as endothelin 1 （ET-1）， ET-3， melanocyte stimulating hormone （MSH）， stem cell factor （SCF）， basic fibroblast growth factor （bFGF） in culture medium after HaCaT cells were cultured by 0.5， 1.0， 5.0 μg/mL of butin for 48 h. RESULTS： Compared with blank control， cell survival rate was increased to varying degrees after cultured by 0.1-5.0 μg/mL of butin for 48 h， while decreased after cultured by 10.0 μg/mL of butin. Contents of ET-1， SCF， bFGF in culture medium were significantly increased after cultured by 0.5， 1.0， 5.0 μg/mL of butin for 48 h （P＜0.01）； and contents of ET-3， MSH in culture medium were significantly increased after cultured by 1.0， 5.0 μg/mL of butin for 48 h （P＜0.01）. CONCLUSIONS： Butin can promote the proliferation of HaCaT cells， the mechanism may be associated with promoting the secretion of cell secretory factors of ET-1， ET-3， MSH， SCF， bFGF.