This study aimed to investigate the relative importance of the psychosocial factors underlying mother's decision to continue exclusive breastfeeding (EBF) for 6 months using the theory of planned behavior. A cohort of EBF-mothers (N = 78) completed a questionnaire assessing theoretical constructs at baseline and phone-interviewed at follow-up. Multiple regression analyses were performed to find important predictors of intention, overall and married vs unmarried. Attitude, subjective norm, and perceived behavioral control together explained 50.2% (P < .01) of the variance in mothers' intention to continue EBF for 6 months. Attitude and subjective norm were better predictors of the intention than perceived behavioral control. The role of subjective norm was greater in married than in unmarried women. A strong, positive correlation (gamma = 0.67, P < .01) was found between intended and actual EBF duration. Intervention programs designed to positively influence mother's attitude and social support may be effective in improving intention, thereby increasing EBF maintenance for 6 months.