Objective To evaluate the effectiveness of a novel traction device in endoscopic submucosal dissection (ESD) for colorectal laterally spreading tumor (LST). Methods Patients with LST treated by ESD in Endoscopic Center of Beijing Chao-yang Hospital of Capital Medical University from August 2018 to April 2020 were enrolled and divided into traditional ESD group (without traction) and traction- assisted ESD group (using an elastic triangle traction device which comprised of 3 clips and 1 rubber band). The total procedure time, submucosal dissection time, submucosal dissection speed and security of the two groups were compared. Results Fifty-four patients with colorectal LST were included, including 29 patients in the conventional ESD group and 25 patients in the traction-assisted ESD group. There were no statistical differences in age, gender composition or lesion location between the two groups (P>0.05). The lesion area of traction-assisted ESD group was larger than that of the traditional ESD group [13.30 (7.55, 15.91) cm2 VS 6.90 (5.50, 13.50) cm2, U=503.50, P=0.014]. The total procedure time [48.00 (35.50, 58.00) min VS 34.00 (29.00, 35.00) min, U=109.00, P<0.001] and submucosal dissection time (39.52±12.37 min VS 25.68±7.37 min, t=4.89, P<0.001) were significantly different between the two groups. In terms of submucosal dissection speed, the assisted-traction ESD group was significantly faster than that of the traditional ESD group [0.17 (0.13, 0.30) cm2/min VS 0.52 (0.30, 0.62) cm2/min, U=604.00, P<0.001]. There were 2 (6.9%) cases of perforation in the traditional ESD group, and no perforation occurred in traction-assisted ESD, but the result was not statistically significant (P=0.493). Conclusion Compared with traditional ESD, traction-assisted ESD with clip and rubber band is safer and more effective in the treatment of colorectal LST.