Abstract: By combining the classic works of Marxist writers about Criticism and Self-criticism and traditional Chinese philosophy on "examination and restraint" and "remonstration", the Communist Party of China formed the fine style of Criticism and Self-criticism in the period of the new democratic revolution. Criticism and Self-criticism have great political advantages and have always been cherished and carried forward in CPC's 100-year of development. In the new ear, Criticism and Self-criticism are the sharp weapons for the Party to maintain its pioneering and pure nature. While promoting the new great project of Party building, we must attach great importance to Criticism and Self-criticism, adopt scientific and correct principles and methods in institutionalizing and normalizing the practice of Criticism and Self-criticism.