A numerical predictor corrector guidance with environmental parameter online identification was proposed for boosting glide missile. Comprehensive environment parameter was introduced in gliding phase concerning both atmospheric density and aerodynamic parameter influence. Extend Kalman filter was used to identify the comprehensive parameter online. Based on identification results, gradual fading-memory recursion least square method was used to build identification model of environment parameter. And the model was gradually revised based on the updated identification. Longitudinal and lateral guidance laws were designed. Drop point was estimated based on the identification model to limit the influence of environmental disturbance. The guidance simulations were carried out with atmosphere density and aerodynamic disturbance. The results demonstrate the identification model can predict the environment parameters accurately and the guidance method has enough robustness to environmental disturbance.