Objective: The paper analyzes the operational characteristics of the “same disease, same price” policy under the DRG payment in A City, as implemented through the urban basic group and the county-level primary group. Methods: Using 2024-2025 DRG catalog data, inpatient medical insurance settlement records, and healthcare institution information, we compared the policy groups with the conventional group across five dimensions: catalog structure, resource consumption, institutional undertaking, cost dispersion, and the "payment standard-cost margin". Results: The urban basic group covered a broader range of DRG, while the county-level primary group was more concentrated in low-weight internal medicine DRG. Both policy groups showed reduced resource consumption and lower cost dispersion compared with the conventional group, but changes in the tier of institutional undertaking remained limited. The urban basic group was predominantly undertaken by tertiary institutions, with a persistently negative "payment standard-cost margin". Conclusion: In the short term, the “same disease, same price” policy primarily manifests as resource consumption convergence and intra-hospital behavioral adjustments, and a single price lever is insufficient to drive patient shifting to lower-level institutions. Policy optimization should focus on catalog refinement by category, referral pathway enhancement, dynamic payment standard calibration, and strengthened coordinated supervision of both costs and quality.