Routing protocols play an essential role in meeting the quality of service requirements in the network, but achieving these requirements may require frequent send and receive operations to build and maintain routing tables, which consume sensors resource If we take into consideration the limitations of wireless sensor networks in terms of the amount of available energy and storage capacity. In this research a performance comparison of the on-demand Distance Vector Routing protocol AODV and Hierarchical Routing protocolHR was carried out in terms of the packet delivery and loose rate, delay and jitter, and the amount of expended energy in the Wireless sensor network operates according to IEEE802.15.4 standard in cases where some of sensors get out of work for limited periods of time. The results showed that the hierarchical routing protocols perform better in terms of delay time and transfer rate and the amount of consumed energy than on-demand Distance Vector Routing protocol routing protocol, but suffer larger packet loss due to routing path corruption as a result of sensors crashes.