Every countries governments in the world is conducting Open Source Software promoting policies to establish fair-competition environment in the software market and to secure technical competitiveness of domestic software industries. The Open Source Software promoting policy is divided into the supply support policy that aims to expand participation of domestic software companies and developers in Open Source Software development projects and the demand promotion policy that aims to establish fair competition environment to improve monopoly and oligopoly structures. The Korean government has promoted the supply support policy including development of Open Source Software technologies and supports for communities and the demand promotion policy including pilot projects, publicity campaign activities for Open Source Software and demand-shaping in e-government projects. As a result, the share of Linux in the server operating system market increased rapidly. Korea's Open Source Software policies focused on spread of Linux at the early stage. And now the focus is extending to development of Open Source Software and demand-shaping in all software spheres.