Abstract: As mental health and well-being are crucial public health issues around the world, the planning and design of green space for promoting mental health have become a key to healthy city construction. With the English literature in the core collection of the WoS database, this research sorts out the progress in studies of the correlation between green space and mental health from three aspects: the influencing factors, impact mechanism, and measurement method. It has shown that there is a multi-factor mixture and multi-mechanism synergy between green space and mental health, and psychological health benefits are mainly generated through three indirect pathways by the characteristics of green space itself and exposure characteristics and moderated by individual and social factors. In light of the contentions of existing studies in indicator thresholds and causal weights, as well as the limitations in disciplinary integration, indicator selection, and data acquisition and analysis, it proposes that future studies should be improved in terms of strengthening cross-disciplinary integration, streamlining the attributes of green space characteristics, emphasizing individual attributes and behaviors, engaging in longitudinal and experimental studies, and introducing intelligent new technologies.