Following the development of clinical trials, the methodology of clinical trials has developed a great deal, including randomization method and blinding method, etc. The method of randomization includes simple randomization, stratification randomization, etc. Dynamic randomization is also considered as a method of randomization. Two dynamic randomization methods are introduced in this paper, including a method considering the balance of numbers in each group and a method considering prognostic factors. This paper also demonstrates the procedure of dynamic randomization of the above two methods by simulations and actual examples.