BackgroundGreen education is an essential precursor to promoting long-term sustainable practices and fostering environmentally conscious behaviours, especially among the younger generations. Such education equips individuals with the knowledge, awareness, and experiences necessary for green behavioural shifts, empowering them to engage actively in sustainable practices in the long run, which is essential for ensuring environmental sustainability. However, green education practices and policies vary among the countries of the Association of Southeast Asian Nations (ASEAN) owing to different levels of socioeconomic development, national priorities, and capacities of each member state. We aimed to analyse and compare the disparities in green education among pace-setter, maturing, and emerging ASEAN countries. MethodsWe used a case-study approach—a desktop analysis based on journal articles, country reports, newspaper articles, and other sources from the past 10 years—to analyse and compare the green education disparities among pace-setter, maturing, and emerging ASEAN countries. FindingsAs a pace-setter ASEAN country, Singapore has made impressive progress in promoting green education through the effective implementation of pragmatic policies and impactful green education initiatives. Furthermore, the country has established extensive formal and informal green education programmes that closely align with the Singapore Green Plan 2030. By contrast, maturing ASEAN countries are making incremental progress in incorporating green education into their formal education systems. However, challenges faced by these countries include a shortage of well-trained teachers, the lack of specific green education subjects in school syllabuses, and financial constraints. Despite these challenges, innovative approaches—such as partnerships with non-governmental organisations (eg, the World Wide Fund for Nature)—have emerged as promising strategies to promote green education within these maturing nations. Emerging ASEAN countries face the biggest challenges in promoting green education. Competing national priorities, political instability, limited funding and resources, inadequate infrastructure, and a lack of qualified educators pose challenging barriers to advancing green education within emerging ASEAN nations. InterpretationThis study provides insights into the best practices and challenges surrounding green education within pace-setter, maturing, and emerging ASEAN countries. To address the disparities in green education among these countries, there is a need to adopt a holistic ecosystem framework characterised by the so-called 8i enablers, namely infrastructure (eg, well-equipped laboratories and learning spaces), infostructure (eg, advanced teaching technologies), intellectual capital (eg, well-trained educators), integrity systems (eg, efficient green education governance systems), incentives (eg, public and private funding for green education initiatives), institutions (ie, strong institutional leaders), interaction (ie, cooperation and collaboration among relevant stakeholders), and internationalisation (eg, leveraging regional and international partnerships to access expertise and resources). FundingNone.