The Belt and Road Initiative (BRI) is a China-led global initiative that was officially launched in 2013. The wealth of research available on the BRI has been subject to few comprehensive reviews to date, reviews including both English and Chinese language research are even rarer still. In addition, many of the projects associated with the BRI involve infrastructure development, power generation and transmission system development leading to concern around environmental sustainability. As a result, China proposed the “Green BRI” concept in 2017 to improve the environmental credentials of the initiative and enhance sustainability, yet the assessment of how the BRI is tied to sustainability is still unsure. In this study, we use the methodology of systematic review to address the following questions: 1) what the overall feature of BRI impact related research is; 2) how have the impacts of BRI been measured; 3) what gaps exist in terms of the scale of impact addressed by the literature; 4) how many studies map with environmental-focused SDGs; 5) what percentage of impact literature on the BRI is focused on environment or biodiversity; 6) is there a language bias between Chinese- and English-language literature. This review provides value as it examines PR and non-PR research to assess how observers in both English and Chinese are prioritizing and presenting the impacts of the BRI to improve understanding of the information available within different decision-making contexts. This study shows that, to date though, there remains no agreed definition or set of matrices of what constitutes green development under the BRI, meaning specific guidance on what can be defined as green (type of project) and what measurement structure is required (including prior informed consent of communities, independent impact assessments, strategic assessments) is unavailable. The BRI research is not discussed along with SDGs or sustainability as we expect. There is scope and need to consider how the sustainability of the BRI can be evaluated so that improvement solutions can be developed for its accountability and sustainability. To add, in both English- and Chinese-language publications, the non-peer-reviewed papers tend toward a more polarized interpretation of the likely impacts of BRI projects whilst peer-reviewed publications offered a more nuanced assessment. Papers in Chinese provide more qualitative discussions of the BRI whilst papers in English give more quantitative assessments. In both languages, the discussion around BRI impacts is qualitative, suggesting a lack of data on which to base quantitative research and develop clear and specific recommendations for action.