Synovial Sarcoma is a rare subtype of soft-tissue sarcoma. The name ‘Synovial Sarcoma’ is a misnomer and suggests an occurrence restricted to large joints of the body. We describe an unusual case of Primary intra-abdominal Synovial Sarcoma in a 15year adolescent who presented to Surgical Emergency of a tertiary care unit with symptoms of gastric outlet obstruction. The patient was stabilized and subsequently exploratory laparotomy was performed for excision of the mass. The final biopsy on histology and IHC confirmed a FNCLCC Grade 3 Synovial Sarcoma with spindle shaped pleomorphic cells. The patient was started on adjuvant chemotherapy after an uneventful surgical recovery. The case highlights the rare incidence of the subtype with an unusual late presentation in the abdomen and addresses diagnostic challenges faced. Synovial Sarcoma , classified under the category of Tumor of uncertain differentiation by the WHO in 2020 1.Various cases reported across the world have proved that in reality the tumor is a carcinosarcoma that can arise from various soft organs anywhere in the body 2. Synovial sarcoma has a relatively low occurrence in the intra-abdominal region, especially intraperitoneal. The diagnosis can be reached by using an optimal immunohistochemistry panel along with histology, in absence of molecular diagnostic services. En bloc surgery with total elimination of the disease remains the treatment of choice due to its aggressive metastatic nature. And further management should be individualized for each patient to prevent recurrence.