In this paper, a multiple model predictive control (MMPC) strategy is applied into an organic Rankine cycle (ORC) based waste heat energy conversion system (WHECS). The rotating speed of the pump and the shaft torque of the expander are manipulated simultaneously to provide the optimal (suboptimal) evaporating pressure and superheating temperature for nonlinear WHECSs under different operating conditions. Simulation results confirm the efficacy of the proposed control scheme.