This study aimed to determine the effect of peer tutoring (PT) in enhancing students’ writing skills during English textbook taught to the students of Grade XI. The true experimental research pre/post-test design was used. The sample of the study comprised of 70 male and 58 female students containing each 35 male peer tutoring group (PTG) and non-peer tutoring group NPTG as well as each 29 female PTG and NPTG after matched before intervention. MCQs related to writing skills developed as a tool for data collection process. The tool is used in both pre and post-test for PTG and NPTG. The difference in both groups was calculated using statistical analysis. Linear regression predicted the effect size of male PTG 16.376 points higher (r = 0.860) than NPTG as well as female PTG 12.183 points higher (r = 0.813) than NPTG. These results indicated that PT technique enhanced students’ academic achievement.