Flexible assembling fixture (FAF) is a new-style assembling equipment in assembly process of aircraft panel components, which is developed based on combination of digitization of assembling and automated modular fixture. The multi-actuator is designed to positioning and clamping the panel component. The dynamic behavior of the FAF is analyzed in process of 3D structure design. The motion and displacement of every actuator are analyzed based on kinematic and dynamic theory, by means of building the Knopoff model taking friction between the vice sport into account. ADAMS is employed to carry out the dynamic simulation. This technical approach is the effective solution for developing the new equipment; moreover, its result presents a great engineering significance in improving the equipment performance.