Imperforate hymen is an uncommon obstructive anomaly of the female reproductive tract for which early diagnosis is easy to miss. Untreated cases after menarche may cause cyclic lower abdominal pain and amenorrhea. Hymenotomy is considered proper management in order to avoid complications associated with late treatment. We report a case of an imperforate hymen in a 13-year-old adolescent girl presenting with tenesmus and acute lower abdominal pain. The patient was treated with hymenotomy and postoperative period was uneventful. Tenesmus and lower abdominal pain resolved immediately after surgery and during follow up the girl reported normal menstrual cycles. According to our case, tenesmus may be an atypical clinical presentation of imperforate hymen. Therefore, imperforate hymen should not be eliminated from differential diagnosis when it comes to adolescent females with abdominal pelvic pain and gastrointestinal symptoms and gynecological examination should be performed.