In recent decades, heated debate around green technology and its equitable access has aroused the concern of international scholars. This paper provides a review on the exclusion of green technology referred to as ‘green techno-apartheid’ and examines selected key eco-cities (i.e. Masdar, Songdo IBD and Bangalore) considered in the 2013 United Nations Environment Programme (UNEP) Report on ‘City-Level Decoupling’ (2013). Metropolitan planning is a crucial instrument in addressing the challenges of urban social sustainability and is thus considered an important mechanism for developing a platform to approach issues of equitable access to green technology. The study reviews five metropolitan plans: the ‘London Plan’ (London, England), the ‘Municipal Plan 2011 for Greater Copenhagen’ (Copenhagen, Denmark), the ‘Economically Strong and Sustainable Structural Vision: Amsterdam 2040’ (Amsterdam, Netherlands), the ‘Hong Kong 2030: Planning Vision and Strategy’ (Hong Kong, China) and the ‘Metropolitan Plan for Sydney 2036’ (Sydney, Australia). The results of the study suggest that while all these plans focus on promoting green technology within a framework of ecological modernisation, they lack appropriate tools for achieving equitable modernisation and enhancing social equity. Consequently, it is essential that researchers and planners take further steps and develop effective instruments to improve equitable access to green technologies and achieve long-term urban social sustainability.