Although small cell base stations (BSs) have been considered to increase network capacity in dense user scenario, it may cause some problems when density of the small cell becomes too much. And then applying full-duplex to a small cell system would be able to provide users with a more consistent quality than just increasing the number of small cell BSs. Conventional system-level evaluation of full-duplex was obtained from average of 1000 runs under randomly dropping small cells. However, in a practical small cell environment, the coverage of each BS vary according to surrounding environment. Therefore, performance analysis based on digital map in realistic scenario is required for accurate evaluation. In this paper, we propose map-based system-level simulation (SLS) methodology for evaluating the performance of full-duplex communications. we used 3D ray-tracing tool (wireless insite) for map-design/network-setup. For realistic simulation, we reflected real-time wireless traffic scenario. Finally, the performance of full-duplex system is compared against of half-duplex system by using proposed map-based SLS.