Xingui Liu,1 Fengting Zhao,2 Linli Hu,1 Yingpu Sun1 1Reproductive Medical Center of the First Affiliated Hospital, Zhengzhou University, Zhengzhou, Henan, People’s Republic of China; 2Clinical Laboratory, the First Affiliated Hospital, Zhengzhou University, Zhengzhou, Henan, People’s Republic of China Abstract: This study explored the value of detection of human epididymis secretory protein 4 (HE4) and carbohydrate antigen 125 (CA125) from serum in diagnosis of early endometrial cancer of different pathological subtypes and discussed the mechanism of HE4 and CA125 in diagnosis. In this study, enzyme-linked immunosorbent assay and chemiluminescent immunoassay were used to detect HE4 and CA125 from serum in endometrial cancer and control groups. Besides, the concentration of HE4 and CA125 was compared in these two groups, and the expression of CA125 and HE4 and clinicopathological characteristics in patients with endometrial cancer were also analyzed. Compared with the control group, the expression of HE4 was much higher in serum of patients with endometrial cancer, while there was no obvious change in the expression of CA125. The threshold detection value was acquired by receiver operating characteristic analysis method, that is, 141.5 pmol/L and 54.5 U/L, respectively. When comparing the concentration of HE4 in patients with endometrial cancer at the early stage (stage I) with healthy people, the difference therein had statistical significance, but there was no obvious difference in CA125. HE4 and CA125 in diagnosis of endometrial cancer in the stages I and II were found with no statistically significant difference. The difference of HE4 in the stages II and III had statistical significance while the difference of CA125 had no statistical significance. The specificity of both HE4 and CA125 was 95%, and the sensitivity of HE4 to uterine papillary serous carcinomas was higher than that to endometrioid adenocarcinoma. Thus, the serum HE4 is much better than CA125 in detecting the endometrial cancer at an early stage. Keywords: HE4, detection of CA125, endometrial cancer