Abstract: Objective To study the role of hepatocyte growth factor (HGF) and its receptor (c-Met) in the pathogenesis of en-dometriosis. Methods In situ hybridization and immunohistochemistry method was used to examine HGF mRNA and protein expression in eutopic and ectopic endometrium obtained from 54 women in reproductive age with endometriosis confirmed by laparoscopy and histological examination (including 28 cases of stages Ⅰ/Ⅱand 26 of stages Ⅲ/Ⅳ) and from the endometri-um of 24 healthy fertile women. Results In patients with endometriosis, the positivity rate of HGF/c-Met expression was simi-lar in the eutopic and ectopic endometria, but the number of positive cells and expression intensity were much higher in ec-topic endometrium. The positive expression rate varied little between the proliferative and secretory stages of the endometri-um. Compare with the healthy controls, patients with endometriosis of stages Ⅰ/Ⅱand Ⅲ/Ⅳhad significantly elevated posi-tivity rate of HGF and c-Met expressions in either eutopic and ectopic endometrium, but without significant difference be-tween the two patient groups (P<0.01). The rate of strong c-Met protein expression was significantly higher in Ⅲ/Ⅳen-dometriosis than in the controls, without statistical difference between other groups. Conclusion The expressions of HGF and c-met gene are correlated with the pathogenesis of endometriosis, which is preceded by eventful changes in the biological be-havior of the eutopic endometrium.