Abstract: Mobile Ad hoc Networks (MANETs) are dynamically vibrant network with the vital issues to be addressed as routing and security. For competent functioning of the network it is essential to establish a secured and topologically stable network. This is achieved by constructing a stable clustered topology based on residual energy calculation and by detecting the malicious nodes using mobile agents. Based on the nodes energy, rank is calculated for each node and the cluster head is chosen by the mobile agents. The mobile agents are checking whether a node is trustable one to participate in the network. Credit system is introduced to increase the trust of the nodes.