意见领袖是网络社区中积极的信息传播者，是社区思想和观点的提供者，为社区讨论设置议程、提供视角，并影响社区成员的舆论导向和态度行为。意见领袖通常拥有某个或多个领域的专业知识和技能，并处于社交网络的中心，能够最大限度的连接社区的关系网络。知乎作为中国社会化问答社区的先锋，鼓励用户分享知识、经验和观点。不同于微博与传统意见领袖，社会身份并非是知乎社区意见领袖的决定因素。知乎特有的投票机制和关注模式催生了大批草根意见领袖，使认真负责的态度、积极主动的参与以及专业优质的答案成为了判定知乎社区意见领袖的关键。本文对知乎社区及其意见领袖的影响机制做了较为详细的探讨，有助于更好的理解网络意见领袖及网络社区的舆论生态。

Online opinion leadersare active communicatorswho are able to set the agenda for online discussions, provide thoughts from different perspective, and possibly change the attitude and behavior of other online community members. Online opinion leaders often are experts in one or more fields, and are in the center of social network. Zhihu.com is an SNS question & answer sites, which encourages people to share knowledge, experience, and ideas. Different from the opinion leaders in Weibo and traditional community, in which social identity is the key factor, the voting system and following mechanism have created a number of grassroot opinion leaders in Zhihu.com. Taking Zhihu.com as an example, this paper intends to examine the social influence of key opinion leaders in online community, and to better understand opinion leaders and the ecology of online community.