Mobile ad hoc networks are growing in popularity due to the explosive growth of modern devices with wireless capability such as laptop, mobile phones, PDA, etc., makes the application more challenging. The mobile nodes are vulnerable to security attacks. To protect the ad hoc network it is essential to evaluate the trust worthiness. The proposed TWCA is similar to WCA in terms of cluster formation and cluster head election. However, in WCA security features are not included. The proposed TWCA is a cluster based trust evaluation, in which the mobile nodes are grouped into clusters with one cluster head. It establishes trust relationship for the cluster based on the previous transaction result. The simulation result confirms the efficiency of our scheme than the WCA and SEMC.