The current study was conducted in the period extending from November 2018 to October 2019 and designed as a case-control study and aimed to assess the seroprevalence of HCMV. However, a total number of 91serum specimens were collected to fulfill this purpose from females (71 breast cancer patients, and control group of 20 females) attending Al-Amal hospital for cancer management and Baghdad teaching hospital and the practical part was performed in College of Science, University of Baghdad. The study protocol was approved by the Ethics Committee at the Department of Biology (Reference: BEC/0220/0011). The immunological part for evaluation of seroprevalence of HCMV was accomplished by ELISA technique which revealed that anti-HCMV IgG was scored positive in 67/71 (94.36%) and 19/20 (95%) of breast cancer patients and control group respectively, whereas anti-HCMV IgM was only detected in 6/71 (8.45%) of the patients of breast cancer. Moreover, levels of IgG were elevated in 81.69% of breast cancer patients compared to 40% only of control group.