Abstract: 【Purpose/significance】This study aims to explore the transmission mechanism of Internet rumors in the event of public re‑ lations crisis, and deeply analyze the impact of characteristics of communication media on rumor transmission. The research signifi‑ cance lies in providing references for theoretical research and practical governance of rumor transmission, so as to effectively evaluate and deal with rumor trust and its subsequent behavior consequences under public crisis situations.【Method/process】The MAIN model and EPPM model are introduced to analyze the information behavior and coping behavior of rumor recipients from the perspec‑ tives of rumor reception stage and reaction stage, and how rumor trust further affects the information behavior and coping behavior of rumor recipients. A conceptual model of influencing factors of rumor propagation based on media characteristics is established, six theoretical hypotheses are proposed, and the model is verified and analyzed.【Result/conclusion】The synchronicity and expression richness of media have a significant negative impact on rumor trust, the immediacy of media and the diversity of information can re‑ duce the public's trust in rumors, the public's dependence on media and the closeness of social connection can increase their trust in rumors, and rumor trust has a significant positive impact on users' coping behavior.【Innovation/limitation】The innovation lies in the combination of MAIN model and EPPM model, starting from the two stages of rumor reception and reaction, systematically analyzing the influence of media characteristics on rumor transmission, and establishing a conceptual model of influencing factors of rumor trans‑ mission based on media characteristics. The limitation lies in the universality and applicability of the model assumptions that need to be further verified.