Utilization rate for the gate and required time and walking distance to boarding flight are important measures for the gate management and passenger's convenience estimation. So, the main purpose of the gate management are the maximization of utilization rate and improvement of airport terminal user's convenience through the efficient gate management. This study intends to maximize the utilization rate of usable gates by considering layout, terminal configuration, local passenger of the airport and development of gate assignment algorithm and DSS which maximizes the gate utilization and minimizes the passengers' walking distance. And the decision support system can provide an efficient means of airport management of airport using an assignment algorithm.