Objective To investigate the therapeutic efficacy and safety of endoscopic resection of giant gastric stromal tumors without explicit evidence of metastases. Methods A total of 12 giant gastric stromal tumors with no evidence of metastases diagnosed by endoscopic ultrasound （EUS） and computed tomography （CT） scan were managed by endoscopic resection. Operation time, blood loss and the incidence rate of perforation were recorded respectively. The diagnoses of tissue specimens were made by pathological examination and immunohistochemistry. In order to assess local recurrence and distant metastases, endosco- py and endoscopic uhrasound follow-up examinations were performed routinely at 2, 6 and 12 months, and the whole abdominal CT scan was also performed at 12 months after operation. Results Endoscopic resec- tions were successfully performed in 10 of 12 cases （83.3%）, among which, 6 underwent endoscopic sub- mucosal excavation （ESE） without unexpected perforation and 4 endoscopic full-thickness resection （EFR） with intentional perforation. The rate of intentional perforation was 33.3% （4/12） , and all the perforations could be sealed by endoscopic methods. The blood losses were all more than 100 ml, which could be con- trolled by argon plasma coagulation, electrocoagulation or hemostatic clips. In the 10 encapsulated tumors, 8 could be smoothly removed from esophagus, whose long diameter of the minimum cross section was less than 3.5 cm, however, 2 tumors whose diameters were larger than 3.5 cm were taken out after segmentation. In the 10 tissue samples ,9 were confirmed as low risk GIST, 1 larger than 5 cm was pathologically confirmed as high risk GIST. During 1-year follow-up, no local recurrence or peritoneal metastasis was found. 2 tumors, larger than 5.0 cm, could not be removed by endoscopic methods due to uncontrolled bleeding. The rate of uncontrolled bleeding was 16. 7% （2/12）. The patients were transferred to surgery, and pathologically con- firmed as having high risk GIST. Conclusion For low-risk giant gastric stromal tumors whose diameters were less than 5cm without evidence of metastases, endoscopic resection is considered as a safe and effective procedure. Tumors with long diameter of the minimum cross section less than 3.5 cm are more suitable for en- doscopic resection, which can be smoothly taken out through cardia. However, for high-risk GIST larger than 5.0 cm, the rate of uncontrolled bleeding is high, so endoscopic resection should be adopted with discretion.