Physician prescribing behavior is an important mechanism through which health policies are translated into clinical practice and is shaped by multiple factors, including individual cognition, social interaction, information environments, and institutional constraints. This paper systematically reviews the major theories and representative models of physician prescribing behavior under health policy interventions, traces their evolution from rational cognition toward cognition–context interaction, and discusses the applicability and limitations of existing theories in the context of China’s health policy practice. The review suggests that classical theories remain insufficient to explain how policy instruments and institutional constraints enter physicians’ decision-making processes and why physicians respond differently to the same policy. This paper classifies health policy instruments into three types: resource allocation efficiency, price and payment regulation, and medical behavior guidance, and outlines their main mechanisms of action and corresponding theoretical pathways. It then proposes a localized refinement strategy that converts physicians’ evaluations of policy and perceived institutional constraints into measurable constructs. Using the Theory of Planned Behavior and National Centralized Drug Procurement as an illustrative case, the study introduces two constructs, perceived policy performance expectations and perceived rigidity of policy implementation and develops a policy-embedded extended model of physician prescribing behavior. Physicians’ professional titles, employment status, and hospital tiers are further incorporated as boundary conditions reflecting institutional stratification. The proposed framework provides a theoretical basis for research on physician prescribing behavior in the Chinese context and for subsequent empirical testing.