Family‐supportive supervisor behaviours (FSSB) and their association with employees' work, family, and health outcomes have been widely investigated in workplace contexts. We aimed to acquire a comprehensive understanding of whether FSSB have valuable associations with work, family, and health outcomes and to investigate how FSSB are related to these outcomes using 126 independent samples retrieved from 122 articles (N = 59,068). Our findings revealed several outcomes. First, the bivariate results demonstrated that FSSB were significantly associated with essential work, family, and health outcomes. Second, FSSB exerted beneficial incremental effects on task performance, burnout, organizational commitment, and job satisfaction beyond coworker support, flexible work arrangements, and family‐supportive organizational perceptions, providing further support for its discriminant validity. Third, we built an integrative model that uses ability‐motivation‐opportunity as our organizational framework. Our findings demonstrate that FSSB are significantly associated with employees' work and health outcomes through self‐efficacy, intrinsic motivation, and autonomy. Intrinsic motivation exerts the largest mean indirect effect, followed by self‐efficacy and autonomy. Based on these findings, we discuss theoretical and practical implications as well as directions for future research.