Abstract: Historical materialism reveals the historical inevitability of the transformation from history to world history and the realization of communism. However, how to understand the specific historical process leading to the Communist society is a major issue related to the development of reality and future society. Therefore, in the critique of Gotha Program, Marx clearly divided the two stages of Communist society and defined the historical span of "transitional period". However, there are two paradigms of understanding about this theory: the "short transition" theory and the "long transition" theory. Through textual interpretation and summary of the experience of historical process, we can see that the former theory shortens the time span of dictatorship of the proletariat, while the latter one blurs tasks and objectives of the first stage of the Communist society. Based on this, this study puts forward the theoretical perspective of "medium transition", which is understood as the period from the proletarian leading revolution to seizing power to "the full development period of the first stage of Communist society". This perspective conforms to the true meaning of Marx and provides scientific theoretical premise for the historical position and practice of the new era of socialism with Chinese characteristics.