Abstract: Around the Nineteenth National Congress of the Communist Party of China, there are two eras, namely, the initial era of socialism with Chinese characteristics and the new era of socialism with Chinese characteristics. Both eras are in the primary stage of socialism, but the main contradiction in the former one is the contradiction between people's growing material and cultural needs and the outdated social production, while the main contradiction in the latter one is the contradiction between people's growing needs for a better life and the unbalanced and inadequate development. Through analyzing the transformation of the main social contradictions in the initial era and that in the new era from the perspective of economics based on the data system, we can clearly see the powerful material and technological basis for the historical transformation of underlying importance, which is also the powerful material and technological starting point for solving the main social contradiction in the new era of socialism with Chinese characteristics and realizing the rejuvenation of the Chinese nation in the future.