Parachute inflation-deployment process is a typical time-varying nonlinear fluid-structure coupling problem. The influence of fabric permeability and initial airdrop velocity was ignored in most numerical models. To modify the calculation model, a finite element model of parachute inflation process was established based on ALE (Arbitrary Lagrange Euler) method and dynamic mesh technology, while permeability and initial airdrop speed preseted. The parachute opening load of C-9 canopy was calculated under finite mass condition and compared to experimental data. While the correctness and rationality of the model verified, the stress distribution and aerodynamic deceleration characteristics was analyzed. Which provided some reference for parachute numerical modeling and structural design.