A 71-year-old male presented with abdominal distension and fever to our hospital. Abdominal CT revealed a huge tumor in abdomen, and non-curative surgery was performed. Peritoneal dissemination was widespread and the tumor invaded the bladder and sigmoid-colon mesenterium. Two months after the initial surgery, CT showed liver metastasis, and oral administration of imatinib mesylate was started. The peritoneal dissemination and liver metastasis showed a decrease, and this was well controlled for 45 months without severe side effects. Abdominal CT revealed peritoneal dissemination in the ileocecum after 43 months since the administration of imatinib. Therefore, sunitinib treatment was initiated. After 3 months of sunitinib administration, the tumor perforated. Emergency operation was performed to resect the ileocecum, and sunitinib was continued for 1 year. In GIST with liver metastasis and peritoneal dissemination, repeated surgical resection combined with chemotherapy is important to improve the patient's survival.