OBJECTIVE: Fear of post-cessation weight gain may be a barrier to cessation therapy or may lead to smoking relapse. This study aimed to evaluate the relationship between the change in eating behavior and post-cessation weight gain. METHODS: A prospective study that included 103 cigarette smokers, who visited the family medicine clinics of a training and research hospital for smoking cessation treatment between June 2018 and December 2018, was planned. A face to face survey (including Turkish version of Dutch Eating Behaviour Questionnaire-DEBQ and weight measures) was applied to all individuals at first and the final visits for the assessment of restrained, emotional, and external eating behaviors. Statistical analyses were completed using the IBM SPSS Statistics 22 program. RESULTS: Of 103 patients screened (M age=38.3 years SD=9.28), 58.3% were male, and 40.8% were in heavy nicotine dependence level (NDL) group. The mean weight increased by 4.74+-2.63 kg in three months of smoking cessation. In the high NDL group, three subscales score (restrained p<0.001, emotional p=0.007, external p=0.005) of the DEBQ increased. Weight gain was significative associated with NDL (p=0.01). There was a positive correlation between Fagerstrom score and weight (kg) gain (r: 0.34; p=0.001). Weight change according to the emotional eating behavior was significantly different by gender (female p=0.005; male p=0.04). Women had a higher difference in emotional eating behavior score than men. Obese smokers had a higher initial restrained eating score than non-obese smokers (p=0.009). Weight gain of nicotine replacement therapy group had a similar result in the pharmacotherapy (varenicline) group (p=0.26). Both of treatment types concluded with a significant weight change (p=0.001).