Chlamydia trachomatis is the most common bacterial cause of sexually transmitted disease and can cause pelvic inflammatory disease (PID), leading to severe outcomes such as ectopic pregnancy, infertility, or pelvic pain. We report a case of a 38-year-old patient with abdominal pain and dyspareunia. Clinical examination revealed diffuse abdominal tenderness. Vaginal and abdominal sonography showed substantial ascites and CA-125 level was elevated. Therefore, the attendant physician performed an abdominal CT scan for further diagnosis. Radiographically diffuse peritoneal enhancement, consistent with peritoneal carcinomatosis, 4-quadrant ascites, and slightly enlarged ovaries with solid and cystic structures were diagnosed, leading to the suspicion of ovarian cancer. In addition, the results of the cervical smear PCR for chlamydia were positive. Due to the positive chlamydia result, the suspicious CT scan, and the young age, we decided to perform a diagnostic laparoscopy as a first step. Intraoperatively, the ovaries were of normal aspect without any cancerous lesions. However, the ascites and the yellow-reddish jelly-like deposits were consistent with acute PID. Thus, chlamydia infection may simulate the presentation of ovarian cancer. Therefore, especially in young patients, we recommend careful scrutiny of every diagnosis of ovarian cancer even if its presentation seems to be typical.