Credit bank system is a very important management mode in current higher vocational education, and it is also an important means for the Ministry of Education to promote China's modern education reform. This paper combines the specific background of higher vocational enrollment expansion, expounds the practical significance of the credit bank system in the training of the expanded enrollment talents, and explores the methods and rules of the authentication and transformation of the learning achievement of the expanded enrollment students under the system. In order to achieve convergence of different types of learning results, smooth talent growth channel, a useful exploration is carried out.