Due to keen competition of medical treatment market and gradual upsurge of patients’ right to medical industries, the manager of medical institutions have started to focus on keeping a permanent smooth relationship with patients. Furthermore, they want to soundly establish patients’ loyalty to medical institutions. To investigate critical factors which affect patients’ will to maintain a solid relationship with medical institutions, we survey outpatients of a regional teaching hospital. 479 effective respondents will be used to empirically analyze the dimension and linear structure equation related to the long-term interactive relationship between doctors and patients. The empirical results reveal that doctor-patient relationship will correlate with mutual social activities. Furthermore, patients’ trust and commitment to doctors will positively affect patients’ willing to maintain a doctor-patient relationship or recommend others. Patients’ trust to doctors significantly affects their willing to raise complaint, and then lower their intentions of complaint. However, patients’ switching barrier is also a critical factor to influence their commitment and willing to be diagnosed with the same doctors again.