A 1-year-old savannah monitor of unknown sex presented after 3 days of anorexia and lethargy. Physical examination revealed an uncomfortable, distended coelom. Radiographs showed a large soft tissue opacity within the central coelom, resulting in compression of the lungs. Ultrasound revealed a large, fluid-filled, multi-chambered structure within the central coelom, suspected to be of ovarian origin. Chemistry and complete blood count were normal. Three days post presentation, coelomic exploratory revealed a large, irregular, fluid filled right ovary, and bilateral ovariectomy was performed. There was no gross evidence of metastasis. Histopathology most closely resembles a granulosa cell tumor, with follicular degeneration on the contralateral ovary. The patient improved and was discharged 2 days postoperatively. Jacobson et al., 2013, and Cardona et al., 2011, reported granulosa cell tumors in a 6-year-old savannah monitor which died 7 months after ovariectomy, and a 9 year green iguana which died 11 months after ovariectomy, respectively. Both cases had tumor regrowth and metastasis at necropsy. Due to recurrence and metastasis noted in those cases, routine ultrasound monitoring was elected in this case to assess for potential tumor recurrence and/or metastasis.