Satellite formation flying with internal forces has attracted great attention for its high performance.However,the control force is highly sensitive to the relative position and relative attitude between satellites,and coupling effect exists between control forces and control torques,both of which pose challenges to building the dynamic model for formations with internal forces.A 6-dof (degree of freedom) relative translational and rotational dynamic model is established in this paper,considering the coupling between control forces and control torques.The cooperative control of relative states between the satellites is realized by designing the control law for both relative position and relative attitude.Finally,the dynamic model is testified through the simulation of formation reconfiguration using the pseudospectral method.