Objective: To evaluate the quality of outpatient prescriptions for Western and proprietary Chinese medicines in a tertiary hospital under the coordinated implementation of DRG/DIP payment reform, the Tertiary Hospital Evaluation Standards (2025 Edition), and the National Performance Assessment of Tertiary Public Hospitals, and to examine the effectiveness of a policy-embedded management model. Methods: A triple stratified random sampling approach (disease category–department–month) was used to collect 4,996 outpatient prescriptions from January 2024 to September 2025. A four-dimensional framework (compliance, economy, efficacy, and risk) was established. Prescription quality was assessed using a risk-scoring model and Apriori association rule analysis. Results: The overall qualification rate was 96.2% (4,807/4,996). The mean number of drugs per prescription was 2.6 ± 0.8; antimicrobial use rate was 16.8%; essential medicines accounted for 62.5%; and drug cost proportion for key DRG/DIP disease groups was 28.3%, all meeting policy targets. Among 189 unqualified prescriptions, inappropriate medication use (38.5%) and minor omissions (48.7%) were the main issues. Association rules identified junior physicians in chronic disease management as a key risk factor (confidence > 40%). Conclusion: The policy-embedded model effectively improved core prescription quality indicators to required standards. Further optimization is needed for special populations, junior physician prescribing, and intelligent system support. The proposed Assessment–Insight–Intervention closed-loop model provides a practical framework for advancing refined prescription management.