Purpose: This study aimed to understand university students' knowledge, attitude and behavior (KAB) toward sustainable development. Design/methodology/approach: A sample of 567 students studying humanities, agriculture or engineering at public universities of Iran participated in this study. A survey was administered to investigate KAB of the respondents according to their gender, membership in academic associations, academic major, educational and informing activities and social units; abbreviated as GAMES. Findings: The results indicated that students had a medium level of KAB, with mean scores of 55.15 out of 75 (for knowledge), 45.68 out of 65 (for attitude) and 36.03 out of 50 (for behavior). Differences and similarities were found on students' KAB by GAMES. The results suggest that education and social units are useful to improve individuals' KAB toward sustainable development. In addition, positive correlations were identified between knowledge, attitude and behavior toward sustainable development. Originality/value: The findings confirmed the key role of education for sustainable development in addressing sustainable development (SD).