Objective:To understand patient family′s acceptance of the online medical platform, the choice of health information access and the influencing factors, and provide a more scientific reference for the construction of the online medical platform.Methods:The literature analysis method, interview method, questionnaire survey method and structural equation model were adopted for research. The subjects of the study were the family members of 204 pediatric patients who were treated at a tertiary children′s hospital. The research content included the patient family members′ acceptance and usability evaluation of the online medical platform, the patient family members′ evaluation of the access to health information, and the sense of control.Results:The system availability scale(SUS)score was 55.355 4±17.454 1, which was at the lowest F level. The patient family′s evaluation of the simplicity of the online medical platform was significantly higher than the traditional approach( P<0.01). In terms of information adequacy and trust evaluation, the patient family′s evaluation of online medical platform was significantly lower than the other two ways( P<0.01). The sense of control is an important factor influencing the acceptance of online medical platforms and the choice of access to health information( P<0.001). Conclusions:The family members of the patients have low acceptance of the online medical platform. On the one hand, medical institutions should continue to strengthen the construction of online medical platforms and adopt a multi-disciplinary strategy to improve the trust of family members in the health information of medical platforms; on the other hand, they should improve the sense of control of patients′ medical procedures.