The patient was a 19-year-old female with chief complaints of right upper abdominal pain and fever who was seen by a general practitioner and was prescribed with an antibiotics without improvement but continued aggravation of symptoms. Upon examination she revealed sign of peritoneal irritation on right upper abdomen. WBC count was 9, 900/μl, CRP 13.5mg/dl, normal gastroscopic study, and some ascites around the liver by sonography and CT studies without abnormal findings in the liver and gallbladder. No free air was present in the peritoneal cavity. A laparoscopic examination performed on an urgent basis revealed the presence of peritonitis, ascites and fibrinous adhesions between anterior aspect of the liver and peritoneum. Accordingly, Fitz-Hugh-Curtis syndrome was suspected and a conservative treatment with minocycline hydrochloride was started resulting rapid improvement of symptoms. Later the diagnosis was confirmed by the presence of positive serum Chlamyclia antibody. In case of peritonitis of unknown etiology in a female patient, a laparoscopic study suspecting the presence of this syndrome is important.