Background: Most gastrointestinal stromal tumors (GISTs) are located in the stomach as submucosal tumors. They are defined as spindle cell or epithelioid mesenchymal tumors of the gastrointestinal (GI) tract. Recently developed immunohistochemical staining methods allow the differentiation of GISTs from myogenic, neurogenic and other mesenchymal tumors. Routine GI screening is well established in Japan and relatively small, asymptomatic GISTs are frequently detected. Although a tyrosin kinase receptor antagonist, imatinib mesylate, has shown excellent results in patients with unresectable or metastatic GIST, surgical resection of the primary tumor is the treatment of first choice when cure is sought. Methods: In our institution ( Keio University Hospital ) laparoscopic wedge resection (LWR) has been performed for the treatment of gastric submucosal tumors (SMTs) since 1993. LWR is the primary procedure for tumors between 2 to 5 cm, while those larger than 5 cm are resected by open methods or laparoscopy-assisted surgery. To investigate the feasibility and efficacy of these methods, the clinicopathological findings and treatment outcome in 60 patients with GIST were analyzed. Results: Among the 60 patients, thirty-five lesions (58.3%) were treated by LWR, 3 by laparoscopic surgery with a small skin incision and 22 by conventional open procedures. The mean size of the tumors was 42.5 mm with a range of 18 to 150 mm. All surgical margins were clear but one case had liver metastases at the time of primary surgery. In the 35 cases of LWR, most patients were discharged uneventfully between 5 to 7 days postoperatively. All patients of the laparoscopically treated group have survived without recurrence on up to 11 years’ follow-up. No port-site recurrence has been encountered. Discussion & Conclusion: Laparoscopic surgery for gastric GIST can be regarded as a minimally invasive, curative and safe method. The literature reported that even incidentally found GIST smaller than 1 cm has mutation in the c-kit gene, especially at exon 11, the most common site in malignant GIST. These findings support the idea that GIST is potentially malignant even when small and emphasize the importance of resection of gastric SMT larger than 2 cm diagnosed as GIST.