Adaptive governance is increasingly considered a feasible approach to address the uncertainties and complexities of social-ecological system (SES), whereas its role on SES coupling has not been sufficiently testified. Empirical evidence is provided in this paper with the case of northwestern China, a region struggling with economic backwardness and ecological vulnerability. Given the ambiguities in scholarship on the causal relationship between adaptive governance and SES coupling, we develop a theoretical framework to outline the driving mechanism of adaptive governance by focusing on its impact on ecosystem service (ES) delivery. Within the framework, ecosystem governance and social system governance are identified as pathways of adaptive governance, which are estimated on their effects on SES coupling by FGLS. The results show that (1) only the synergy of them can positively promote SES coupling rather than isolated one of them, and (2) only social system governance presents a lustrous role in restraining the effect of resource-dependence on SES coupling as opposed to ecosystem governance. The practice of northwestern China again evidences its key leader’s role in seizing the opportunity window and social innovation. The results further uncover the necessity of synthesizing the social and ecological dimensions for shaping adaptive governance and the direction of targeted reforms for catalyzing the transition to adaptive governance.