Abstract: Objective : To study the expression of hMSH₂ in endometrial carcinoma. Methods : The expression of hMSH₂ protein was analyzed by immunohistochemical technique in 104 cases of endome-trial carcinoma, 35 cases of normal endometrium (17 proliferative endometria, 18 secretory endometria) and 8 cases of atypical hyperplasia. The relationship between the expression of hMSH₂ and clinico-pathologic characteristics of endometrial carcinoma were also investigated. Results : Loss of hMSH₂ ex-pression was detected at 5.9% in normal proliferative endometrium, 5.6% in normal secretary en-dometrium, 50% in atypical hyperplasia and 68.3% in endometrial carcinoma. The differences between normal endometrium and endometrial carcinoma and between normal endometrium and atypical hyper-plasia were statistically significant. There was no statistically significant difference between cancer and atypical hyperplasia. The rate of expression of hMSH₂ was lower in endometrial carcinoma than that in other histological types (P=0.035). The 5-year survival rate for patients with negative expression of hMSH₂ was 80%, higher than the 52% seen in patients with positive expression. The prognosis for pa-tients with negative expression of hMSH₂ was better. Conclusion : Loss of I1MSH₂ expression may be re-lated to the early development of endometrial carcinoma. The rate of hMSH₂ expression was lowest inendometrial carcinoma. The prognosis of patients with negative expression of hMSH₂ was better than that for patients with positive expression.