Recently,some research suggest that narrow banding imaging and endoscopy ultrasonography are considered established means of diagnosis for early gastric cancer and depth.No formal quantitative review of the available evidence has been published that narrow banding imaging or endoscopy ultrasonography could accurately diagnose early gastric cancer and evaluate the invasive depth.This means still has great limitations.The sensitivity of narrow banding imaging diagnosis is only 60% which its high false positive rate,shorter wavelength and lighter penetration,and the result is influenced by histologic variety of early gastric cancer and inflammatory changes in the background mucosa;Although endoscopy ultrasonography achieves a diagnostic accuracy of over 80%,and its tomographic views facilitate objective assessments,it is occasionally difficult to obtain images with adequate quality, and its evaluation is highly dependent on operators' proficiency levels.