A 27-year-old unmarried woman with acute intermittent abdominal pain for 6 hours without nausea, vomiting or fever.Urination and defecation were also normal. No leucorrhea was found in this patient. Pelvic examination appeared tobe normal. Others physical examination revealed tenderness with mild guarding at right lower abdomen. Laboratoryfindings: hemoglobin 10.8 g/dL, white blood cell 11.73 103/μL , Neutrophil 80.1%, Lymphocyte 14.4%, Monocyte 3.1%,Eosinophil 1.0%, and platelet was in normal range. Provisional diagnosis was acute appendicitis versus rupture of ovarian cyst.Pelvic Ultrasonogram was chosen to be primary imaging revealing moderate amount of fluid in pelvic cavity and extended toboth lumbar gutters and the appendix was not identified. Consequently, MRI pelvis was performed instead, the findings showedrupture of right ovarian cyst (see Fig. A). Management was conservative treatment and follow up with MRI imaging untilcomplete absorption of fluid in pelvic cavity. (Fig. B-C).