The Republic of China was a key period of the development of Confucianism. The Imperial Examination was abolished and the discipline of classics disintegrated, so that intellectuals produced different understandings on traditional Confucianism. There were four understanding dimensions: Confucianism is a kind of religion; Confucianism is a kind of classic; Confucianism is a kind of system; Confucianism is a kind of lifestyle. The dimension of religion, on one hand, promoted Confucianism to the height of religion; on the other hand, maintained the social foundation of Confucianism. The dimension of classic reflected an academic style in the inheritance of Confucianism. The dimension of system was a misunderstanding for Confucianism under the context of the culture conflict between China and the west. The dimension of lifestyle aimed at building a traditional Confucian lifestyle. In the period of the Republic of China, these different understanding dimensions of Confucianism provided different approaches for the modern transition of Confucianism. Nowadays, these approaches still constitute the mainstream of Confucian development.