There are two transitions of Marx and Engels Thought.The first transition is that from Revolutionary Democratism to Communism,from Idealism to Materialism.This transition started from the articles in the period of the "Rhine",The Outline of Feuerbach,and German Ideology finished in 18451846.The second transition is that after the formation of Marxism.The paper examines and narrates the concept of the "Asian Mode of Production",and its position and historical change in social developing sequence,and historical change in the view of the fate of Capitalism,and in the thought of the possibility of the Russian commune overstepping the "Kafidin's Capitalist Valley".