Hematometrocolpos is accumulation of blood in the vagina and uterine cavity due to intra-uterine hemorrhage. A 20-year-old female presented to our clinic with massive menorrhagia at menarche after progestin usage. Hematometrocolpos was detected by transabdominal ultrasonography. She was pale because of heavy bleeding for 5 days and hemoglobin level was measured as 5.1 g/dl. Initial treatment was blood transfusion and medical drug therapy. After resolution of the hematometrocolpos was shown by transabdominal ultrasound 2 days later, the patient, who was stable, was discharged without complication. Obstruction of the female genital outflow tract is rarely seen. Hematocolpos has been reported in elderly women following vaginal occlusion due to radiotherapy, vaginal fibroma and labial synechiae causing infection or inflammatory conditions. The case is presented here because of the successful management of hematometrocolpos due to massive dysfunctional uterine bleeding in a young virgin patient.