Nowadays, due to the popularity of portable computers and the increasing demands of users to access computing services in a better way is required. Mobile ad hoc networks (MANET) are self-configuring wireless networks with no established infrastructure. Due to constantly changing network architecture, a lack of central monitoring, and insufficient security mechanisms, MANETs are vulnerable to a variety of attacks. The primary objectives of this study are to detect a node’s misbehavior in a MANET and also effectively validate the selfish node by using an algorithm for detecting selfish nodes. Retransmission is reduced and all network metrics performance is increased resulting from the discovery. AODV was utilized as the routing algorithm in this study. Using the NS2 simulation tool, the proposed algorithm is implemented. In the presence of selfish nodes and without selfish nodes, our proposed algorithm improves the packet delivery ratio, and throughput, and minimizes delay and packet drop, which are all network metrics that are compared and examined. The simulation analysis evaluated based on the routing performance was enhanced in the proposed AODV protocol in terms of packet dropped, packet delivery ratio, end-to-end delay, and throughput. However, the study of the simulation result showed an improvement in packet delivery ratio from 85.60 to 87.6638, an improvement of packet dropped from 34.40 to 32.38, the throughput improved from 674.52 to 724.521 and end-to-end delay improved from 1.902 to1.08. We concluded that all performance parameters investigated by the proposed Selfish node detection algorithm demonstrate improvement.