Abstract: The thesis tries to demonstrate the Right theory of Hayek compared with other liberalisms. Firstly, by a historical description of the Right theories of social contractive and Utilitarianism, the important status of the concept Right in the whole liberalism is proved. And then, we point out that in Hayek's theoretical horizon it is not appropriate to regard Right as the basic concept by which proving and protecting liberty. Secondly, we try to expound Hayek's thought of Negative Right in which the Rule of Just Conduct has a core status, and as a comparison we also reveal the thoughts of Positive Right of the Neo-liberals represented by Rawls, analyzing the reason that they have epistemology approaches of Constructivist Rationalism which opposite to Hayek's epistemology approach of Evolutionary Rationalism. Lastly, we expose the differences in the theoretical approach and thinking manner between Hayek and Neo-liberals and show the reasons as well. By the discussion of Right Theory of Hayek, the thesis has also given comments and criticisms on the relevant positive Right Theories.