Objective: To evaluate the leading role of hierarchical diagnosis implementation in the construction of compact county medical communities in a province. Methods: Qualitative comparative analysis was used to retrieve the data indicators of a province in 2021 from the national compact county medical community performance evaluation monitoring system as the study variables. Results: By analyzing the effects of five conditional variables on the implementation of hierarchical diagnosis in the construction of compact county medical communities in a province，three dominant effects were derived. The leading role of medical insurance fund，the leading role of general practitioners，and the leading role of county medical community construction were the leading roles influencing the effect of hierarchical diagnosis within a province' s compact county medical community. Conclusion: It is needed to give play to the leading role of medical insurance fund to promote the implementation effect of hierarchical diagnosis，pay attention to the cultivation of medical talents and improve the system of general practitioners，build and improve the information platform of county medical communities to promote the construction of compact county-type medical communities.