Participative behaviors of online community (OC) members affect development of OC deeply. Lurkers are reported to make up a sizable proportion of many online communities, yet little is known about their reasons for lurking. Without insight into lurkers, our understanding of behaviors of OC members is incomplete. Ignoring, dismissing and may lead to inappropriate design of online environments and Knowledge sharing between members. To investigate lurking on Wikipedia, the authors carried out a study of online survey to find the reasons of lurkers lurk.