ABSTRACT Background: The integration of naturalized players in Chinese soccer since 2019 has sparked significant debate, with mixed results raising questions about the effectiveness of this policy in improving the national team’s performance. Objectives: This study aims to analyze the differences in physical morphology and athletic performance between local and naturalized players in the Chinese Super League to assess the impact of naturalization on the national team’s competitiveness. Methods: Utilizing the AMISCO computerized tracking system, we collected and analyzed data from 561 matches spanning the 2019-2021 seasons. Employing mixed linear models, we examined the variance in key physical morphology and performance-related variables, with standardized differences assessed through Magnitude-Based Inference (MBI). Results: Our findings indicate modest but significant differences in physical morphology between local and naturalized defenders (P < 0.05, -0.32 < ES < -0.42). Performance-wise, naturalized defenders outperformed local counterparts in both technical and tactical aspects and demonstrated superior high-intensity running capabilities. Similarly, naturalized midfielders showed a slight edge over local midfielders in technical, tactical, and running proficiency. Conversely, local forwards exhibited marginally better technical and tactical performance compared to their naturalized counterparts, albeit with minimal differences in running ability. Conclusion: This study reveals that while naturalized players demonstrate certain advantages in physical morphology and athletic performance compared to local players in the Chinese Super League, these advantages are not consistent across all positions.