Objectives: To evaluate the use of serum prolactin as a tumor marker in diagnosing uterine fibroid(s). Methods: A case control study was carried out from March 2010 to October 2010, at El Kasr El-Aini University maternity Hospital. Thirty patients with uterine fibroid(s) and 30 healthy normal women were involved in the study. Blood samples were collected from uterine fibroid patients before and after surgery. The serum prolactin was measured by ELISA technique. Results: The serum of patients with uterine fibroid before surgery showed an elevated prolactin level (57.43 + 57.85) compared with their prolactin after surgery (21.16 + 16.04), and with the control group (12.43 + 4.67). This also increased with increasing the fibroid number, size and duration of fibroid related symptoms, independently of the site or the type of the fibroid. Conclusion: Serum prolactin can be used as an adjuvant biochemical marker to confirm the diagnosis of uterine fibroid(s).