The invention of Social Networking Site not only changes the way people searching information and communicating, but also business marketing strategy. Before Social Networking Site came out, the usual way business marketing strategies are TV commercials, print advertisements and activities. After Social Networking Site got popular, more and more businesses turned to use the Internet as a strategy of marketing because the cost is inexpensive and it is easier to gain potential clients through the whole world. One of the Internet’s characteristics is virtually, which is a difficulty for business to run their website because they cannot actually observe their customers’ behavior. In this study, we try to use the data that we collect to analysis the behavior of iCook fan Page’s fans based on Dialogic Theory. Dialogic Theory has five facets, Dialogic Loop, Usefulness of Information, Generation of Return Visits, Ease of the Interface and Conservation of Visitors. Most of the studies used content analysis to analysis the criteria they defined, we define the criteria form user’s perspective and collect the data in a more convenient way. Moreover, we attempt to find out the relationship between Dialogic Theory and the change of fan number. The study found out that some criteria have relationship with fan’s number, which means if a business wants to improve their public strategy on fanpage, they can start from looking for these criteria. These criteria can help a business to run their fanpage more effectively; it also helps to gain fans’ value on the Internet.