The vehicular ad hoc network (VANET) is the self-configuring network due to which security is the major concern that affects network performance. Due to such nature of the network, malicious vehicles enter the network which triggers various types of security attacks in the network. The security attacks can be generalized into active and passive attacks. Various schemes have been designed so far which detect malicious nodes from the network and increase the security of VANETs. Among all the designed schemes, trust-based mechanism is reliable and secure to increase security of the network. The behavior analysis and Hidden Markov Model (HMM)-based trust management scheme is proposed for the VANETs to increase security. In the scheme, based on the vehicle behavior trust is calculated. The scheme is much more reliable which is proved through various parametric values. In this research work, behavior analysis and HMM-based trust management schemes will be improved so that the behavior of the vehicles will be analyzed in a more efficient manner. To analyze the behavior of the vehicles, various parameters will be considered like the number of packet exchanges, neighbor of vehicles, and delay. It is expected that the proposed scheme will increase the security of the network.