Abstract
Public sphere is an important idea of Habermas in the early research, which guided his latter research, especially in political philosophy field. According to Habermas’ research on public sphere, this paper researches public sphere’s significance in solving the legalization crisis of capitalism and remedying the democratic theory of bourgeoisie. Public sphere idea set up a new model of the democratic theory, deliberative democracy, which is better than democracy of both liberalism and republicanism, and become the most important theme of Habermas in theory and practice.