The use of straddle carrier in container terminals can reduce the operation links and reduce the types and quantity of terminal mechanical equipment， at the same time， the setting of buffer capacity is very important. Firstly， in order to reduce the overall completion time of the terminal， improve the operation efficiency of the terminal， as well as solve the spatial-temporal coordination problem caused by joint loading and unloading operation of using straddle carrier as horizontal transportation equipment with quay crane， the dual-cycle operation strategy was introduced and joint operation sequence optimization problem of quay crane and straddle carrier was studied. Secondly， a mixed integer programming model was established to minimize the total completion time. In the model， the practical constraints of dual-cycle operation of quay crane and straddle carrier， as well as the constraints of the buffer capacity of quay crane and safety time were considered. Thirdly， aiming at the limitations of traditional Tabu Search （TS） algorithm， an greedy algorithm based reactive TS algorithm was designed by introducing greedy algorithm， multi-neighborhood search method and reactive algorithm， and numerical experiments were conducted. Experimental results verify the effectiveness of the proposed model and algorithm. Finally， through the experimental analysis of the number of buffer capacity and straddle carrier， the ratio of quay crane and straddle carrier， the optimal number of straddle carriers and buffer capacity， as well as the ratio of quay crane and straddle carrier were obtained. The results show that compared with traditional terminal equipment configuration， the dual-cycle operation strategy can reduce the number of straddle carriers and improve the utilization rate of quay crane and straddle carrier.