The growing teratoma syndrome (GTS) was originally defined by Logothetis et al. in 1982 as a phenomenon of subsequent growth of the benign tumor, following the removal of a primary malignant tumor during or after chemotherapy with normalization of previously elevated serum tumor markers and absence of any non seminomatous germ cell tumor components. To date, only a few case reports of ovarian GTS have been documented in the medical literature. There are two reported cases of GTS in Tata Medical Center, Kolkata. The first patient was a 21 years old girl - diagnosed as immature teratoma after staging laparotomy in July, 2016 for complex right adnexal mass. She successfully completed four cycles of chemotherapy in November, 2016. A year later, she underwent debulking surgery for complex pelvic mass with calcifications and fat in imaging but with normal tumor markers. Cut section showed multiloculated cyst with hemorrhagic, mucinous and calcified areas with teeth formation.?Final histopathology showed mature teratoma elements only suggestive of Growing Teratoma Syndrome. The second patient was a 50 years woman diagnosed as ovarian immature teratoma post TAH-BSO followed by completion of chemotherapy in?2001. Follow up imaging in June, 2017 showed right sub diaphragmatic mass but with normal tumor markers clinically looks like Growing Teratoma Syndrome. Subsequently, she had excision of right sub diaphragmatic solid mass and final histopathology showed mature teratoma elements only suggestive of Growing Teratoma Syndrome. Complete surgical excision is the treatment of choice. GTS has an overall good prognosis. However, close follow up is essential even after the treatment.