As a new discipline, Chaos theory was ushered in the revolution in physics of the 20th century, which is of jistoric significance. Chaos theory is concerned with the objects in our tangible world (macro world) with the measure of human beings. In this paper, a brief analysis of chaos theory and fractals is given and then the enlightenment and new perspective for urban planning from chaos and chaos theory are illustrated. The author hopes that!this paper could draw the concerns of designers regarding the application of chaos in urban planning.