Objectives: Gastrectomy with lymph node dissection is the stare4rd treatment for early gastric cancer(EGC). However, patients who have high risks demand modifications in surgical treatment for EGC. Recently, endoscopic mucosal resection(EMR) has become accepted in many institutions as a treatment for cancerous mucosal lesions of the stomach. Thus we investigated the efficacy and safety of EMR prospectively in the patients with EGC who have high risks in surgery and those with premalignant lesions. Method: Twenty-five patients were treated with EMR, thirteen were EGC and twelve were premalignant lesions such as tubular adenoma, severe dysplasia. We used standard snare method and endoscopic mucosal resection using a band ligation kits(EMRI.), Resuts : The complete resection rate at the first step of EMR was 100%(13/12) in premalignant lesions, 76.9%(10/13) in EGC. Of three EGC resected incompletely at the first step, one patient was treated by surgery and two patients underwent the third step of EMR. The final complete resection rate was 92%(23/25) and it was 100%(12/12) in the premalignant lesions, 84.6%(11/13) in RX. We final complete resection rate in according to the methods was 100%(5/5) by standard snare method, 75%(6/8) by EMHL, As pathologic results, all cases of F were limited to the mucosa. No serious complications such as perforation, major bleeding were encountered. Conclusion: We consider that EMR is effective and safe in treatment of the patients with EGC who have high risks in surgery and those with prernalignant lesions.