In recent years, it has been reported that several existing networks including the Internet have scale-free structure. In this paper, through a simple numerical analysis, we investigate effect of the scale-free structure of communication networks on their end-to-end performance. As network topologies, a random network and a scale-free network with the equal number of nodes and the equal number of links are used. We compare end-to-end performance of flows (i.e., throughput) in both random and scale-free networks. Consequently, we show that when the average degree of a network is small (i.e., whah the number of links is small), a scale-free network shows better end-to-end performance. On the contrary, when the average degree of a network is large (i.e., when the number of links is large), we show that a random network shows better end-to-end performance.