This study aims to investigate predictors of successful smoking cessation with demographic profiles, physical and physiological variables, smoking behaviors, and psychological variables. Participants were 73 smokers (65 males, 8 females) participated in an hospitalized smoking cessation program whose mean age was 44.89 (SD=9.61). Participants completed questionnaires and psychological tests including: Fagerstrom Test for Nicotine Dependence, Eysenck Personality Inventory, Multidimensional Coping Scale, and Jerusalem and Schwarzer's Self-Efficacy Scale. And data from variety of clinical measurements were included for analysis. Data Mining Answer Tree was performed with 43 variables. Results revealed that active coping, renunciation, obstinacy, psychoticism, neuroticism, body weight, and sleep disorder were significant predictors for successful smoking cessation till 1-year after hospitalized smoking cessation program. Active coping were most determinant variable for long-term successful smoking cessation. These results suggest roles of psychological variables for long-term successful smoking cessation.