This research aims to explain the factor of difference in each policy between John Howard and Kevin Rudd. There is a significant differences on policy towards immigrant in each era. The method of the research uses qualitative analysis based on textbook, e-book, e-journal, report, news, and article. Perception theory can explain the reason why the policy was different. The ideology of each prime minister using the theory explains the cause of difference. Conservatism and Howard can not be apart because Howard belief on the ideology since his childhood. While communitarianism make Kevin Rudd be a more humanist people. Then he launch the policy of Big Australia which controversial in Australia. The phenomenon explains that ideology of the people can bring them to different decision.