Gastric inflammatory myofibroblastic tumor (IMT) is an extremely rare lesion with mimicking malignant features and accompanied with various clinical manifestations. Here we present a 2-yr-old boy who had a gastric IMT with a huge extragastric mass, which closely resembled a neuroblastoma on imaging studies. He experienced intermittent fever and poor appetite for 6 weeks. Fever remained up to 38 degrees C even on the operation day. He underwent partial gastrectomy and distal pancreatectomy with splenectomy including the tumor. The preoperative fever disappeared and did not recur in the postoperative course.