Hydrosalpinx is one of the predisposing factors of adnexal torsion. However, because the incidence of hydrosalpinx in adolescent virgin patients is very rare, it may cause diagnostic dilemma, leading sometimes to suboptimal treatment. We present the case of an 18-yr-old female, not sexually active, presenting with acute lower right abdominal pain. The working diagnosis was of a simple ovarian cyst, so aspiration was performed. Abdominal symptoms reoccurred and sonography revealed a large hemorrhagic cystic mass adjacent to an edematous right ovary. The patient was referred to immediate laparoscopy due to suspected right adnexal torsion. On laparoscopy, the right adnexa was twisted three times causing an edematous ovary with a hematosalpinx. Detorsion was performed. Five weeks later, transabdominal ultrasound reviled normal bilateral ovaries and the hematosalpinx disappeared. In conclusion, hydrosalpinx, although very rare in adolescence, must be considered in the differential diagnosis. Aspiration in such cases is not the treatment of choice and moreover, it may cause complications.