The recommended dose of imatinib for recurrent gastrointestinal stromal tumors (GIST) is 400mg/day. However, adverse effects limit the use of the standard dose in elderly patients. We report a case of an elderly patient with recurrent GIST, where long-term control of the disease was achieved with low-dose imatinib therapy. An 86-year-old man presenting with tarry stool was admitted to the hospital; upper GI endoscopy revealed a gastric submucosal tumor of the stomach at the posterior wall of the cardia. Partial gastrectomy was performed laparoscopically. The submucosal lesion was histopathologically diagnosed as malignant GIST. Administration of imatinib was initiated 17 months after surgery because of recurrence of GIST. The initial dose of imatinib was 400mg/day, which was later adjusted to 200mg or 300 mg/day because of adverse effects. Though imatinib was withdrawn several times due to strong side effects, the disease was well controlled for 6 years after surgery.