The efficiency and success of wireless systems which make use of sensors to collect information is determined by the data quality of collected sensing data. One of the most effective factors on the data quality is false information which may result from the malfunction of sensor boards, unreliable wireless communication channel and compromised sensors. Vehicular Ad hoc NETworks (VANETs) which are a particular application of highly dynamic sensing systems has emerged with the main purpose of improving the safety of passengers and roads. In these networks, equipping vehicles with computers, global positioning system and wireless communication devices have enabled emergency information dissemination through vehicle-to-vehicle (V2V) and vehicle-to-RSU (V2R) communications. Malicious vehicles in VANET may disseminate rumors and attempt to provide false information such as reporting fake events causing other vehicles to make incorrect decisions and wrong moves. Due to safety concerns, a crucial point is how to trust the information transmitted, in other word, how the false information could be detected. To resolve this problem, many researches have focused on trust management. Some of proposed trust models have used reputation schemes applied to mobile ad hoc networks (MANETs). But due to the ephemeral nature of vehicular networks, reputation schemes cannot be sufficiently suited to the VANETs. Some others have used data-centric trust models. These models efficiency also clollapses when the network area is sparse or when collusion attack happens. Based on the researches have been done so far, in VANETs, its almost unattainable to introduce a completely distributed trust management system which could be able to retain all its functionalities in highly dynamic parts of the network where the neighboring vehicles are rapidly changing and moving in and out of range, or when collusion attack exists. In this project, we propose a bogus information detection system for VANETs in which vehicles’ honesty reputation is saved in the RSUs’ common database and every vehicle asks periodically for its reputation from the nearest RSU.In this system, when vehicles report a message, they attach their honesty reputation and their neighboring vehicles’ ID to the message. The message receiver evaluates the reliability of the message based on the reporter vehicle’s justify; MARGIN: 0cm 0cm 0pt" Key words Vehicular ad hoc network, malicious behaivior, trust management, fuzzy inference system