PolyCystic Ovary Syndrome(PCOS) is an important cause of androgen excess, menstrual irregularity, and cardiometabolic dysfunction in women. iLong term manifestations such as gynaecological malignancies, like endometrial carcinoma increased to more than three folds due to endometrial hyperplasia resulting from chronic anovulation and obesity. Cancer antigen 125(CA125)glycoprotein mucin in nature tumour marker is valuable in screening for ovarian and endometrial malignancies, monitoring therapy, early detection of recurrence and, prognosis of these cancers. This study is arranged as PCOS women are considered risky group and CA125 early screening may make a change in the type of treatment..This study was done in Iraq in 2019 between July and October Forty women aged 18-42 year were included they were distributed into two groups, PCOS group, and non PCOS group. BMI was within normal for both groups. Blood samples were taken in early follicular phase for assessing luteinizing hormone (LH), follicular stimulating hormone (FSH) and free testosterone (FT) hormone. Other blood samples were taken at late follicular phase to calculate CA125levels using enzyme linked immunosorbent assay (ELISA). This study revealed no significant difference in CA125 between normal group and PCOS group .In spite of the hormonal disturbance in PCOS and increasing risk of malignancy, CA 125 was not increased in non-cancerous patients