Diversity has described as one of the key issues in communications policy. This paper will discuss, by using 2003-2008 IX Internet rating data in Taiwan, the internet market performance. The performance was calculated by the amount of website category supply and demand. The website category supply are defined as the website which are the internet user visit most frequently.(based on the quantity of page view) The demand of website category are defined as the ARO amount of Internet Websites that are adopted by IX Internet Panelist. By analyzing the website category supply and demand, the finding is the diversity of Internet Website’s supply has shown stability to certain extent during the past seven years. The diversity of Internet Website’s demand has increase tremendously.This result has shown that Internet User in Taiwan has shifted their website usage from Internet ISP,searching engine, and etc to social netwok category that has combine the function of strong interaction,Vedio and Photo sharing, online entainment, and small-scaled business operation. And the findings can be applied for the internet marketing either on Advertising agency or Advertiser.