Hong Kong news media regulation followed the British media regulation and forming the basic ideas of deregulation in post-war era after it has been changed several times. This paper pointed out that the basic trend of Hong Kong news media regulation is liberalization, commercialization, and internationalization. The change process of regulation is led by multi-factors, such as the political ,cultural, economic,technological and other factors, and the most important factor is the changes of political environment. At the same time, in the change process, game among the various interest groups also affected the formation and development of regulation. At last, this paper compared the news media regulation in Hong Kong and the Mainland of China, as a way to consider the Media Regulation Reform in the Mainland of China.