The six degrees of freedom dynamic and motion models of the parachute recovery system were built. In order to solve the problem caused by the lack of measurable experiment data, the genetic algorithm was designed to estimate the aerodynamic parameters of the parachute. Simulation result validates the feasibility of the estimation method and the validity of the estimation model. The aerodynamic parameters of a large ringsail parachute applied to manned spacecraft were estimated through the genetic algorithm and the analysis data from the videos of airdrop test. Furthermore, the stability of the ringsail parachute was analyzed through the estimation results. The conclusion can provide theoretical reference for the design of recovery system.