Heterogeneous network will be the network of thefuture because of the disadvantages of the traditionalcellular networks.High power, high mobility traffic, low capacity andlow coverage area are the most important disadvantageswhich face the traditional cellular networks. Also toomany users demanding too much data is a big problem intraditional cellular network. Future networks willsupport huge mobile data traffic, support low mobilitytraffic, interwork efficiently with other radio technologies. Future networks will also be low power andenvironmentally friendly. Another technology will solve most problems oftraditional cellular network. It is Wireless Sensor Network. Wireless sensor networks are made up of number oftiny mobile nodes, which have the capability ofcomputation, sensing and Wireless networkcommunication. All of these techniques help to development of the structure of cellular networks and to construct the fifth generation of mobile service structure. In this paper the problems that face the cellular network and how to overcome these problems by using Heterogeneous Network and Heterogeneous Wireless Sensor Networkand the structure of these networks.