Objective To explore the clinical and pathological features of laterally spreading tumor （LST） in colon， and the efficacy and safety of endoscopic submucosal dissection （ESD）. Methods A total of 376 cases with 403 lesions of LST were detected by colonoscopy in the First Hospital of China Medical University from April 2014 to December 2016. The site， size and classification of all lesions were recorded. One hundred and sixty lesions in 143 patients underwent endoscopic treatment， and Their pit pattern were observed. The resected lesions were sent for pathological examination. The patients were followed up regularly after treatment. Results Among 403 cases of LST， 168 lesions （41.69％） were located at rectum， which was the main site. Lesions with diameter of 10-＜20 mm were of the largest number （37.22％， 150／403）. Nodular mixed type was the main morphologic type with a total of 203 lesions （50.37％）. The main pathologic type was low-grade adenoma （65.51％， 264／403）. The malignant potential rose with the increase of diameter of LST lesion （P＜0.05）. Compared with the LST granular type， LST non-granular type had a higher pathologic malignant potential （P＜0.05）. Among 403 lesions in 376 patients， 145 lesions in 128 patients were treated by ESD. Intraoperative bleeding occurred in 12 patients， and no delayed bleeding or perforation occurred. Among the 160 treated LST cases， Ⅳ-type pit pattern was of the largest number， up to 70.62％ （113／160）. The canceration rate of Ⅴ-type pit pattern was the highest， up to 80.00％ （8／10）. Malignant degree of pathology （P＜0.05） and penetration degree of cancer （P＞0.05） showed an increasing trend with the upgrade of pit pattern of LST cases. Among the 128 patients who were treated by ESD， 113 cases were regularly reexamined， and 2 cases relapsed. Others whose wounds didn′t relapse healed well. Conclusion The clinical and pathological features of colorectal LST are unique. ESD is an effective and safe treatment for LST， which can achieve radical results.