Abstract-This study is concerned about how to optimize the production sequences to minimize the makespan in hybrid flow shops with limited intermediate buffers. An improved memetic algorithm (IMA) is proposed for solving the NP-hard problem. In this algorithm, the method of generating the initial population, the local search procedures, the selection, crossover and mutation operators are newly designed. Optimization results are compared between the IMA and other three scheduling algorithms proposed in previous literature. Comparison results show that the IMA proposed in this paper is feasible and efficient for scheduling hybrid flow shops with limited intermediate buffers.