As the most appropriate data processing method of ambient intelligence, wireless sensor network has a broad space of application. One of the most important applications of wireless sensor network is fire rescuing in building, and there are many special technology requirement for this application. In order to resolve nodes uneven distribution and exactly estimation the location and intensity of fire, a target oriented distribution routing protocol based on LEACH, which is called LEACH-TOD, is proposed. LEACH-TOD improves the cluster heads selecting process of traditional LEACH protocol, and offsets the defects of LEACH protocol on rationality of cluster heads position and communication quality in cluster in the uneven nodes distribution. The proper clustering structure is formed through node density measuring analyze and threshold limitation to provide effective and rational routing structure for information collecting. The experiments prove that the LEACH-TOD protocol prolongs the whole lifetime of the network and serves to the accuracy of fire field parameter model foundation.