Purpose: This study was conducted to identify factors for smoking middle school students` intention to quit smoking on the basis of the social influence and self-efficacy [ASE] model. Methods: Data were collected from 2,015 students from five middle schools in Daegu with a structured questionnaire in March, 2013 and analyzed by using x2-test, ANOVA, pearson`s correlation and multiple regression analysis. Results: The smoking rate was 6.1% among the total subjects and 85.4% of the smokers had intention to quit smoking. The mean value of attitude toward quitting smoking was 2.15±0.34, that of social influence 3.38±0.65, and that of self-efficacy 2.84±0.95. The multiple regression analysis showed an explanatory power of 24.7%, and experience of trying to quit smoking was the strongest factor affecting the intention to quit smoking (β=.34, p<.01), followed by school years and social influence. Conclusion: In order to increase smoking middle school students` intention to quit smoking, intervention strategies are needed to increase positive social influence or to offer public information to younger smoking students in low school years.