There has been significant progress in improved adolescent sexual and reproductive health and rights (ASRHR) for girls across low- to- middle-income countries (LMICs). However, progress has been uneven, and disparities persistent across and within countries. For example, Vietnam is one of only nine countries to have achieved the 2015 maternal mortality rate (MMR) target of the Millennium Development Goals (MDGs) as a nation, but for some sub-populations, progress has been much slower, and MMR is more than twice that the national average. Ensuring equity is a current focus of the Sustainable Development Goals (SDGs) agenda that seeks to Leave No One Behind. This paper explores some of these inequities and potential drivers for ethnic minority adolescent girls in Vietnam, with a specific focus on the Tay community, the largest ethnic minority group in Vietnam. This paper highlights the challenges to progress, including areas where there is still limited evidence about the range of socio-cultural factors that may determine sexual and reproductive health outcomes for Tay adolescent girls. In the era of the SDGs, Vietnam’s national policy platforms and current aid architecture provide a solid basis on which to build research, policy and practice investments that improve the health of adolescent ethnic minority girls in Vietnam.