Transformation process to Audience-centered Communication Theory is introduced, as well as the basic idea of the theory in China. It is believed that using Audience-centered Communication theory can help to consolidate the theoretical basis of participatory agricultural extension. The communication essence of agricultural extension activity is studied, which is spreaders send information to farmers; then, farmers filter and process the information, transform it into their own experiences and feed back on time. Internet logical relationship between audience-centered communication and participatory agricultural extension is studied. Effects of Audience-centered Communication Theory on participatory agricultural extension are analyzed. One is that the Audience-centered Communication Theory defines the guidance and implementation basis of agricultural extension activities; the other is that bringing Audience-centered Communication Theory into agricultural extension research can help to expend the agricultural extension. Several enlightenments of the theory to participatory agricultural extension are obtained. Firstly, take audience as the orientation and focus on the needs of the audience. Secondly, advocate the participatory approach of process; and emphasize the importance of internal audience participation. Thirdly, establish two-way interaction mechanism; and make the promoters understand the implementation and performance status on time. Fourthly, develop vernacular knowledge; and better integrate the innovation and practice.