Objective To evaluate the clinical usefulness of magnifying endoscopy with narrow-band imaging in distinguishing neoplastic from non-neoplastic colorectal lesions，using the JNET classification. Methods A total of 110 lesions detected by conventional colonoscopy were enrolled in this prospective study. Each lesion was assessed by ME-NBI，and the histology was predicted according to characteristics of vessel pattern and surface pattern with JNET classification and Kudo classification，respectively. The results were compared with actual histologic findings of these lesions. Results The diagnostic sensitivity，specificity，PPV，NPV，and accuracy of the overall JNET classification with ME-NBI were 96.2%，93.8%，97.4%，90.9%，and 95.5%，respectively. Those of the overall Kudo classification with ME-NBI were 92.3%，81.3%，92.3%，81.3%，and 89.1%，respectively，with no statistically significant differences(P=0.077). Diagnostic accuracy of JNET classification was 92.3% in the 1 to 5mm group，93.8% in the 6 to 10 mm group，98.2% in the more than 10 mm group，with no statistically significant differences(P=0.379). Conclusion JNET classification with ME-NBI is effective in distinguishing neoplastic from non-neoplastic colorectal lesions.