Abstract: Kang Youwei's ideas on the theory of human nature contained three parts: (1) the natural theory of human nature;(2)the theory of reasonable feelings and desires;(3)the theory of changing temperament. Kang Youwei's ideas about the theory of human nature carried on the essences of ancient Chinese theories of human nature,western bourgeois-democratic ideas and the theory of evolution, and advanced further.

Key words: Kang Youwei, the theory of human nature, feelings and desires, temperament