Human freedom is closely related with his will. It not only emphasizes human subjectivity, autonomy and voluntary, but also asserts peoples social responsibility and obligation. In the history of human thought, depending on the basic viewpoint of historical materialism, Engels first scientifically revealed the connotation of freedom and free will. Free will is the dialectical unification relations with morality: Free will can endow with the moral implication for human behavior, and morality can give freewill to rational scale; freewill is the logical premise of moral shame produced, and moral shame can also promote the sound development of freewill.