Endoscopic submucosal dissection(ESD) is a widely accepted treatment for early gastric cancer(EGC),especially in Korea and Japan.The criteria for the therapeutic use of ESD for EGC have been expanded recently.However,attention should be drawn to the technical feasibility of the ESD treatment which depends on a lesion’s location,size or fibrosis level,or operator’s experience.In the case of a lesion with a high level of difficulty,a more experienced operator is required.Thus,the treatment for a lesion with a high level of difficulty should be performed according to the degree of the operator’s experience.In this paper,the authors describe the ESD procedure for lesions with a high level of difficulty. Endoscopic submucosal dissection (ESD) is a widely accepted treatment for early gastric cancer (EGC), especially in Korea and Japan. Criteria for the therapeutic use of ESD for EGC have been expanded recently. of the ESD treatment which depends on a lesion’s location, size or fibrosis level, or operator’s experience. in the case of a lesion with a high level of difficulty, a more experienced operator is required.Thus, the treatment for a lesion with a high level of difficulty should be performed according to the degree of the operator’s experience. In this paper, the authors describe the ESD procedure for lesions with a high level of difficulty.