So many complex phenomena have emerged from economic and social systems that traditional economics and management science can do nothing about them. For resolving the problems under the environment of complexity, scientists have been trying to search the routine of coping with complex problems since the 1970s. As the result of their efforts, five schools of science of complexity can be identified. So in this paper, the five schools are compared systematically. The thoughts and theories of the schools are analyzed respectively. Finally, the developed and applied foregrounds of the schools of complexity are prospected.