Gastric liposarcoma is an extremely rare tumour that usually affects the extremities and retroperitoneum. Preoperative diagnosis is difficult, and operative procedures are not well standardised. A 61-year-old woman presented with melaena, epigastric discomfort and palpitations. Upper endoscopy revealed a submucosal tumour at the posterior gastric fundus with an actively bleeding ulcer on the top. Our preoperative diagnosis was lipoma, and we performed laparoscopic intragastric surgery. However, the histopathological diagnosis was liposarcoma. Laparoscopic total gastrectomy was performed to achieve a wide surgical margin. Several recent series have shown that a positive microscopic margin is associated with a higher rate of local recurrence than a negative margin. We have added a staged operation to obtain a wide margin in cases involving a positive surgical margin. Preoperative diagnosis of liposarcoma is still challenging. Gastric lipoma-like tumours should be resected with a wide margin because of their possibility of malignancy.