Flow dynamics of pulp fiber suspensions can be used to describe the flow and forming processes of a modern paper machine and provide a theoretical basis for the optimization design of papermaking process and equipment. In this paper,the characteristics,model and simulation method of pulp fiber suspensions are introduced,and the relevant measurement techniques are expounded. Then,a flow dynamics is proposed to investigate multiphase flow-pulp fiber suspensions by combining new measurement techniques with advanced software. Moreover,the recent theoretical research results in the field,which are achieved by the authors and their team and entitled "Investigation into Flow and Simulation of Pulp Fiber Suspensions in Various Models and PIV Measurement Technique”,are specially presented. Finally,this paper elaborates on the applications of the above-mentioned theoretical results to the structure optimization of the head box and forming device during the process of developing a domestic high-speed paper machine.