The popularization of higher education is a concept of unity of quantity and quality. The increase in the number means that the enrollment rate of school-age youth should reach 15%-50%. Qualitative change includes a series of changes, such as the change of educational concept, the expansion of educational function, the diversification of training objectives and educational models, the curriculum, teaching methods, admission conditions, management methods and the relationship between higher education and society. Martin Trow, an American scholar, believes that if the gross enrollment rate of higher education is taken as an index, the development process of higher education can be divided into three stages: elite, popularization and popularization. He believes that when the gross enrollment rate of higher education reaches 15%, higher education will enter the stage of popularization.