This study addresses robust regulation problem for piecewise affine systems with bounded additive disturbances. Robust tube–based model predictive control strategy is used to separate the nominal system from the uncertain system and then maintain the disturbed trajectory of the uncertain system in a tube around the nominal system trajectory. Accordingly, an algorithm is proposed based on robust tube–based model predictive control strategy to enlarge the region of attraction without increasing the prediction horizon by changing the terminal constraint set. This algorithm enlarges the region of attraction without computational complexity of increasing receding horizon. Simulation examples, including two different case studies, are given to illustrate the effectiveness of the proposed robust tube–based model predictive control.