Effective flight boundary control will be helpful to prevent loss-of-control in flight. A model reference adaptive control method based on linear parameter varying (LPV) model is studied for flight boundary protection. An affine parameter dependent LPV flight dynamics model (FDM) is built up by function substitution method. The mismatch between LPV and full-quality nonlinear FDM can be decreased with the variation of scheduling parameters. The problem of real-time flight boundary protection can be solved by constrained generalized predictive control. Furthermore, a numerical algorithm is designed to protect the boundary of control surface deflection and its increments, flight states, etc. The simulation results show that the instantaneous dynamics response of LPV model can approximate that of nonlinear FDM. Flight boundary protection can be implemented effectively by constrained predictive control numerical algorithm.