In current wars, supply systems have become vital factors to reach military success. With improvements in technology, the capabilities and means of military units have also improved and as a result, the supply materials which military units require have also increased greatly. The timely delivery of supply materials to the combatant units is the key to success. The delivery of supply materials to combatant units at the right time and as needed can only be possible with the efficient planning of supply systems by staff officers. The insufficient evaluation of supply systems will cause interruptions in delivery of supply materials to combatant units and consequently prevent the combatant units from accomplishing their tasks. In this study, the existing ammunition and fuel supply systems of an armored battalion before alarm order is evaluated via simulation. By using the simulation models which were coded for existing systems, commanders will have the capability to detect potential problems and take precautions. The main objectives of this study are: (1) To evaluate existing systems via simulation because of difficulties in executing real world systems due to impediments in creating real world conditions and also economic reasons. (2) To detect the factors which have significant effects on the existing system. (3) To foresee the probable problems of the existing system by studying the simulation model outputs using statistical methods. (4) To select the most critical region of Turkey according to performance measures of interest. The codes of models are created by using ARENA 3.0 simulation program and SIMAN programming language.