Abstract: The great founding spirit of the Communist Party of China (CPC) is put forward based on four periods: the period of celebration, during which the centenary of the founding of the CPC is celebrated; the period of development, during which the goal is to build a great modern socialist country in an all-round way; the period of propulsion, during which Party building is the new great project in the new era; and the period of transformation, during which the world witnesses the great changes unseen over the past century. The great founding spirit of the CPC has profoundly answered the following questions from four dimensions, "why was the CPC established?" "where is the CPC heading to?" "what action will the CPC take?" and "for whom does the CPC serve?" The spirit is embedded by profound thoughts and rich connotations, presenting an organic integrity with rigorous logic and internal coherence. The great founding spirit of the CPC is originated from the Party's ideology and theory, condensed in the historical development of the Party, and formed in the process of the Party's practices. To promote and develop the great founding spirit of the CPC in the new era, we should take the theory construction as the foundation task, equip ourselves with thoughts and theories. Besides, we should rely on the historical resources of the Party, focus on the history of the Party over the past century. Finally, we should integrate ourselves into the course of struggle and practices to enhance the persuasive power, affinity and influence of the great founding spirit of the CPC.