中文摘要：

社会化媒体时代的到来，不仅仅是一种技术的更新，还极大地改善了信息的传播环境。社会化媒体环境下，危机事件呈现出易受民众关注、易“异变”、传播效果放大等新特性，需要进行深入研究。从社会化媒体环境下危机事件传播的新特性出发，探讨社会化媒体环境下的危机事件在危机事件类型、参与主体、发表渠道、民众抗争措施4个方面的非对称性现象，并分析了社会化媒体下危机事件发展各阶段非对称性现象的表现。最后，为政府避免社会化媒体环境下危机事件非对称性，有效控制危机事件事态提出相应对策。

英文摘要：

The advent of the social media era brings the society not only a technical update, but also a great improvement of the informa-tion spread environment. Under the present new social media environment, crisis events are apt to be focused by the public, easy to ＂change＂, and have enlarged communication effect, these and other new features call for in-depth study. Starting from the new features of the spread of the crisis event in social media environment, this paper discusses the information transmission asymmetry phenomena from 4 aspects of crisis event type, participants, participation channels of the subject, and popular resistance measures taken by the public. Then, the paper analyzes the asymmetry phenomena related to the different stages of development of the crisis event. Finally, the paper puts for-ward some corresponding countermeasures to help government to avoid the asymmetry effect of crisis event under social media environment and control the crisis situation effectively.