Endoscopy is commonly used to inspect gastrointestinal disease.The traditional white light endoscopy(WLE) has limitations on the detection of mucosal lesions and is likely to misdiagnose or never diagnose.Advanced endoscopy technology is beneficial to distinguish between the lesion and surrounding mucosa,and make the subtle lesion of mucosa surface and microvascular easily to be found.This article reviews the clinical diagnoses application of gastroscopy in the mucosal lesions of the upper gastrointestinal tract.