As the work focus and central tasks of the party and the state in a specific historical stage are determined by the main contradictions of society, it is necessary to study on and adapt to the new changes in the main contradictions in Chinese society. The transformation of the main contradictions in the society of the new era is the result of the contradiction movement between productivity and production relations, and supply and demand sides. It reflects the development and changes in our country's productivity and the historical evolution of production relations in the new era, as well as the inherent contradictions between supply-side and demand-side structures. To adapt to the transformation of main social contradictions and to grasp the law of transformation, we must take development as the fundamental principle in adapting to the changes in the main contradictions in Chinese society. Moreover, we should adhere to the fundamental political stance centered on the people and the fundamental way to implement the new development concept, as well as the inevitable requirement of the supply-side structure reform.