Public policy implementation is a complex process transforming ideal texts into real-world actions, involving the interaction of multiple factors. Traditional research has predominantly focused on objective dimensions such as policy instruments, implementation environments, and institutional design, relatively neglecting the psychological and behavioral mechanisms of policy implementers, thereby falling into the theoretical dilemma of “de-subjectification.” As agents with agency, policy implementers’ role perceptions, behavioral strategies, and value preferences constitute critical variables influencing policy outcomes. Yet these remain marginalized due to their elusive quantifiability. Originating in social psychology, role theory emphasizes how individuals’ positional identities within social structures shape their behavior, offering systematic conceptual tools for understanding policy implementers’ actions. This paper constructs a typological framework for policy adaptation centered on the analytical thread of “role construction—role conflict—role adjustment”, categorizing policy adaptation into seven ideal types. Using case studies of task force mechanisms in grassroots policy implementation, it dissects the behavioral logic and adaptation strategies of implementers navigating multiple role tensions. The study demonstrates that role theory not only effectively identifies the causes and types of policy adaptation but also provides an actionable analytical pathway for policy implementation research, partially addressing existing research gaps.