This paper proposes a new evaluation model considering cost based on a cost parameter to evaluate the performance of cellular system. One of the issues of the next generation cellular systems is the improvement of cell-edge throughput performance. In order to improve the cell-edge throughput performance and to extend the coverage area, relay transmission is becoming a promising technique. The cell-edge throughput performance degrades because the signal from the base station (BS) becomes weak due to the large propagation loss and large inter-cell interference. By using relay transmission, cell-edge throughput performance improves because it can reduce the propagation loss. However, the larger number of relay station (RS) increasing the total cost. The cost of each RS is relatively low compared to the cost of the BS because of its simple structure. Thus, the performance evaluation considering RS cost is important in terms of whether to introduce RSs in cellular systems or not. In this paper, we propose a simple evaluation model considering cost to assess the total performance of multi-cell cooperative multi-hop cellular systems.