Objective: To explore the correlation between the occurrence of tubal pregnancy and the expression level of leukemia inhibitory factor (LIF) and LIF receptor (LIFR). Methods: Semi-quantitative analysis of LIF and LIFR by immunohistochemistry was performed in 11 fallopian tubal tissues of non-pregnant group,and 36 of tubal pregnancy group,respectively. Results: The LIFR expression level in fallopian tubal epithelium cells of tubal pregnancy group was significantly higher than that of non-pregnant group. While the LIFR abundance in interstitial cells of tubal pregnancy group was significantly lower than that of non-pregnant group. However,no significant difference of LIF abundance was found between two groups. Conclusion: Aberrant expression of LIFR in oviduct tissues might be involved in the ectopic implantation process of tubal pregnancy.