As the carrier of preoperative communication and health information transmission, auxiliary tools directly affect the quality of patients' perception of medical treatment. The development in the age of digital intelligence has further improved the digitalization level of communication tools, but the influence of the fidelity of health information on communication quality and its potential mechanism still need to be studied. Therefore, this study discusses the influence of health information fidelity on doctor-patient trust, and explores the synergy between picture types and information fidelity. Focusing on the operation of nevus excision in dermatology, we recruited subjects (N=318) and conducted a 2 (picture type: static/dynamic) ×3 (fidelity: low/medium/high) inter-group experiment, and discussed the effectiveness of preoperative communication tools from the dimensions of health information awareness, doctor-patient communication experience and trust. The results show that there is an interactive effect between the fidelity of health information and picture types, and the medium fidelity of health information and dynamic pictures are the most beneficial combination for patients to understand and communicate with their doctors. In addition, information awareness and communication experience play a chain intermediary role in the process that the fidelity affects patients' trust.