The WWW, has become a fertile land where anyone can transform his ideas into real applications to create new amazing services. Therefore, it was just a matter of time until the massive proliferation of virtual communities, social networks, etc. New social structures have been formed by massive use of new technologies. This way, people can relate to other by interests, experiences or needs. In a scenario where WWW has become more important every day, and people is using more often the web to relate to others, to read news, obtain tickets, etc. The need of well organized web sites has become one of the vital goals of enterprises and organizations. To accomplish such task web mining area was born more than a decade ago. Web mining are techniques that help managers (or web sites’ experts) to extract information from a web sites’ content, link structure or visitors’ browsing behavior. This way, it is possible to enhance a web site, obtain visitors’ interests patterns to create new services, or provide very specific adds depending on the navigation preferences of visitors (recommendations systems). In the beginning of the Web, web sites were formed by static pages, this means contents were created usually by the owner of the web sites, or the web masters. These contents usually did not change very much through time since it required effort from administrators. Today, a new paradigm arose, we have a participative Web. The web has evolved to the point that it is composed by dynamic contents created by millions of users collaborating one to each other. Sites like, youtube, Blogger, Twitter, facebook, orkut, flickr, among many other, are part of the social web sites’ phenomenon. For example, twitter had 475,000 members by Feb. 2008 while it had 7,038,000 members by Feb. 2009, which means 1382% of growth. Facebook on the same dates passed from 20,043,000 members to 65,704,000 members which means 228%. The use of web intelligence techniques to explode data stored in these social web has become a natural approach to obtain knowledge from them. Since volumes of data are huge, the use of web intelligence techniques was the natural approach to obtain knowledge from social web sites. However, to study members of a social web site is not only to study a group of people accessing a web site and working together; they establish social relationships through the use of Internet tools allowing the formation shared identity and a shared sense of the world. In order to provide truly valuable information to help managers, web masters and to provide better members’ experience when using the social web site, it is necessary to take into account datas’ social nature in web mining techniques. This chapter focuses on the application web intelligence techniques in combination to social network analysis to study of social web sites. In order to provide truly valuable informaton from social web sites that support a social entity. We show that new techniques need to be focused on the study of underlying social aspects of those social entities to really exploit the datas’ social nature and provide a better understandig of human relationships.