An efficient MPC algorithm with larger attraction region is presented for discrete-time linear systems subject to input constraints. Firstly, the larger attraction
regions of MPC are computated by augment state-space models. Then, the line-search optimization algorithm within the MPC framework is designed to solve on-line optimization problem. This algorithm guarantees the early termination and monotonically decrease properties of the cost performances. Meanwhile, the local convergence of the line-search optimization algorithm in MPC and asymptotic stability of close-loop systems are proved. Finally, a numerical simulation shows the effectiveness of the algorithm.