Runway capacity is an important indicator of the level of airport services. Because of simple runway taxiway structure in small and medium-sized aviation airport, runway occupancy time is longer while aircraft taking off and landing is the main factor affecting airport capacity. Detailed aircraft landing, taxiing time and introduced of regulatory rules, the capacity evaluation model considering runway and taxiway structure was proposed. Programming with Visual C++ for numerical simulation, the results show that the model quantified the key factors acting the airport runway capacity and runway occupancy time, such as real rolling distance, taxiway location, taking off and landing proportion In Ganzhou airport, for example, the model of capacity evaluation results accord with actual flight principles and control rules, to improve the airport throughput to provide technical support, has certain reference value and practical.