Growing teratoma syndrome (GTS) occurs during post-treatment observation of ovarian malignant germ cell tumors. The characteristic features of this syndrome are normal tumor marker levels and evident tumoral mass or implants on imaging studies. We report a case of GTS in a 22-year-old woman with a malignant germ cell tumor. After staging surgery and chemotherapy, computed tomography showed peritoneal implants. Laparoscopy was planned to exclude malignant recurrence. During laparoscopy, smooth and pink-colored lesions were seen at the lateral pelvic wall. Histopathologic evaluation reported mature teratoma tissue with extensive mature glial components. GTS is not a malignant condition and the benefit of radical surgical intervention in cases without mass-related complication is not proven. GTS should be kept in mind after primary treatment of ovarian immature teratoma.