HE4, known as human testicular secretory protein 4, is a new tumor marker, which is highly recognized as another tumor marker for epithelial ovarian cancer after CA125.HE4 is not expressed in normal ovarian surface epithelium, while it is highly expressed in plasma ovarian cancer and endometrioid ovarian cancer.HE4 combined with CA125 has a high clinical value for early diagnosis, disease monitoring, postoperative recurrence monitoring, and differential diagnosis of benign tumors in epithelial ovarian cancer.HE4 also has a certain sensitivity for endometrial cancer. HE4 and CA125 are of high clinical value in the early diagnosis, disease monitoring, postoperative recurrence monitoring, and differential diagnosis of benign tumors.HE4 also has a certain sensitivity in the diagnosis of endometrial cancer.