Multi-node model of canopy and parachute system under axisymmetrical hypothesis was set up according to their structural and mechanics characteristics. Dynamics equations of this model for simulating inflation process of flat circular parachute with no angle of attack have been constructed by considering the effect of stress, gravity and pressure. On the assumption that the evolvement of fluid field is quasi-steady, the pressure values on the canopy at selected moments were calculated out by solving RANS(Reynolds averaged navier-stokes) equations of RNG(renormalization group) ��k-ε�� turbulence model with simple algorithm. With the combination of dynamics equations code and CFD(computational fluid dynamics) program, the fluid-structure interaction study of a selected parachute was carried out, and the change of its shape and characteristics was simulated. The feasibility of multi-node model is confirmed by analyzing calculated results and comparing them with those from some other researches. A new method to study the fluid-structure interaction of parachute is established.