By analyzing the ideas of Marx——his ideas on the sources and phenomena of“Political Despotism”、“Economic Despotism” and on the ways of how to eliminate “Economic Despotism” and to realize Liberation for the Human being,this article shows the magnificent meaning of Marxist’s establishment of historic materialism from the revolutionary democratism to communism based on the view points of “Economic Despotism”,and at the same time summaries Marx Value pursue in his whole life.