Purpose/Significance Based on the extended TAM-TPB integrated model, the main factors affecting patients’ willingness to participate in the first diagnosis at the grass-roots level are studied. Method/Process The structural equation model is used to analyze the influencing factors and the internal mechanism in the decision-making process of patients’ choice of primary care. Result/Conclusion Patients’ subjective norms, behavior attitudes, and perceived behavior control significantly and positively affect their willingness to participate in the first diagnosis at the grass-roots level, perceived ease of use and perceived usefulness significantly and positively affect their behavior attitudes and perceived behavior control, and perceived ease of use significantly and positively affect their perceived usefulness. There are blind spots in patients’ cognition of the first diagnosis at the grass-roots level and their sense of self-efficacy is weak. It is necessary to continuously strengthen the systematic publicity of the relevant policies and regulations of the first diagnosis at the grass-roots level, simplify the process and steps of the first diagnosis at the grass-roots level, guide the residents to establish a scientific and rational concept of medical treatment, so as to strengthen the willingness of patients to participate in the first diagnosis at the grass-roots level.