Abstract: Objective To systematically evaluate the impact of the "group-based " medical assistance program for Xizang, conducted by Peking Union Medical College Hospital, on the implementation outcomes of standardized residency training (SRT) at the Xizang Autonomous Region People's Hospital, and to provide evidence-based decision-making references and policy optimization recommendations for medical education support models in border ethnic minority regions. Methods Using Donabedian's quality-of-care theory as the analytical framework, a systematic evaluation was conducted across three dimensions-structure, process, and outcomes. Qualitative research methods and work documentation analysis were comprehensively employed to assess the key interventions, implementation processes, and training outcomes of the "group-based " medical assistance program, centered on the core strategy of "full-time secondment and backbone downward deployment," implemented by Peking Union Medical College Hospital during the 2025-2026 period at the Xizang Autonomous Region People's Hospital. Results Through the core strategy of "full-time secondment and backbone downward deployment," systematic safeguards for SRT institutional development were achieved, effectively promoting the standardization of teaching activities and the establishment of a multidimensional, full-coverage faculty training system. Concurrently, the establishment of a three-tier teaching supervision mechanism further consolidated the connotation and quality of the SRT program. These measures have played a positive role in enhancing the SRT system construction, improving trainees' clinical competence, and strengthening faculty teaching capabilities at the Xizang Autonomous Region People's Hospital. Nevertheless, future SRT implementation in the Xizang region still requires further refinement in precision management, with curriculum design and rotation scheduling more adequately tailored to local circumstances, so as to continuously promote the long-term sustainable development of SRT quality. Conclusions The "group-based " medical assistance program for Xizang, underpinned by the strategy of "full-time secondment and backbone downward deployment," has demonstrated a significant facilitating effect on improving SRT quality in the Xizang region. The experiences and outcomes derived from this program may provide a valuable research foundation and policy evidence for future medical education support initiatives in other border ethnic minority regions, including Xinjiang and Xizang.