This paper aims to analyze changes and characteristics of the Chinese Communist Party (CCP)'s ideology after reform and opening up by studying the trend of the sninicization of Marxism. Especially, in the paper, the period since reform and opening up are divided into two stages: the first stage (1978-2006) and the second stage (2007-present). In the first stage, the ideologies employed by the CCP have ex post facto characteristics to address its identity issue caused by adopting market economy and to maintain the party's cohesion. On the other hand, since 2007, the CCP has improved its ideologies based on the theoretic system of socialism with Chinese characteristics, which have consistent and expansive characteristics compared to ideologies in the first stage. This change in the sinicization of Marxism provides a possibility that the CCP can maintain its position as a ruling party despite of decreasing economic growth.