As the most basic public service, medical and health service is an important support to cultivate and strengthen the sense of national identity. In this paper, based on the data of the Comprehensive Survey of Chinese Social Conditions in 2021 (CSS2021), the linear regression model is used to study the public's cognition of the macro system of medical and health services and the influence of the physical practice in the process of medical treatment on national identity. The study found that there was a significant positive correlation between the public perception of the macro system of medical and health services and the sense of national identity. The better the public perception of medical safety, medical equity and local government's quality of medical services, the higher the public satisfaction of medical insurance, and the higher the sense of national identity. In terms of the physical practice in the process of public medical treatment, the choice of public medical institutions has a significant impact on the sense of national identity, and the choice of public hospitals for medical treatment has a higher sense of national identity. The study did not find a significant relationship between the feeling of medical institutions and the sense of national identity. We should take health governance as an important window to test the modernization of the national governance system and governance capacity, start from the public health promotion, continue to improve the ability of the medical and health service system, focus on guaranteeing the fairness and justice of the medical and health service system, vigorously promote the humanistic care of medical and health services, so that the public can feel the sense of gain, happiness and security in the process of medical and health services. Constantly generating national identity.