The document studies the effects of malicious nodes on the performance metrics of Mobile Ad-hoc Networks (MANETs), specifically focusing on throughput, packet drop rates, and average latency using the AODV routing protocol. Through simulations involving various node configurations and malicious behaviors, it reveals that network performance declines as the number of malicious nodes increases, resulting in higher packet loss and latency. The findings emphasize the importance of identifying and isolating malicious nodes to maintain effective communication within the network.