We are reporting a case of Mullerianosis, which presented as a multiloculated cystic mass on the serosal surface of the fundus of the uterus. Clinically and radiologically, this was interpreted as an ovarian tumor. Mullerianosis is a very rare benign tumor-like lesion. Awareness of this lesion is necessary to avoid misdiagnosis by clinicians, radiologists, and pathologists.

Keywords: Fundus of uterus, Mullerianosis, multiloculated cystic mass