This study examined individual and institutional factors impacting the outcomes of sustainability education in a local university in Hong Kong. Adopting a pre- and post-test design, we found students scored 10.25%, 2.69%, and 0.68% higher on environmental knowledge (p = 0.000), environmental dispositions (p = 0.027), and daily conservation behaviours (p = 0.316), respectively after taking the general education course, "Energy: Today and Tomorrow" at City University of Hong Kong. Advancement in environmental knowledge, stronger environmental dispositions, and pro-environmental behaviours were inter-related and the former was positively associated with the latter. Furthermore, outcomes of environmental education were contingent upon a subject's learning strategy and socioeconomic status. Policy implications for creating enabling conditions to maximize the benefits of environmental education and pursue Hong Kong's long term sustainability were also discussed.