The IEEE 802.15.4 and ZigBee protocol stack offers great potentials for ubiquitous and pervasive computing, namely for Wireless Sensor Networks. However, there are still some open and ambiguous issues that turn its practical use a challenging task. One of those issues is the study of low power consumption of sensor device, which is the biggest issue in sensor network, still has many unresolved issues. Another issues is how to build a synchronized multi-hop cluster-tree network, which is quite suitable for QoS support in WSNs. In fact, the current IEEE 802.15.4 and ZigBee specifications restrict the synchronization in the beacon-enabled mode to star-based networks, while it supports multi-hop networking using the peer-to-peer mesh topology, but with no synchronization. This paper, based on IEEE 802.15.4 and ZigBee as sensor network solution, suggests slotted beacon scheduling(time division beacon scheduling Approach in ZigBee Tree Networks.) for low power consumption within a network environment which consists of hierarchical tree topology and beacon-enabled network. To perform multihop transmission, the ZigBee sensor network consists of tree topology and beacon enabled network. The purpose of such multihop beaconing network is to provide a chance to sleep for routing nodes and minimize power waste. We need beacon transmission scheduling in order to reduce power waste and prevent any collision at the time of beacon transmission.