A Mobile ad hoc network (MANET) is stated as a self-configured, infrastructure-less, continuous collection of mobile devices connected to form a network without using wires, as no pre-existing infrastructure is required for setting up it. A MANET performs its operation as a multihop process between the sender and receiver, because of which they became highly vulnerable to security attacks. DDoS (Distributed denial of service)is one of such attacks which is an active attack in a MANET, whose main goal is to prevent the availability of network services from their legitimate users. In DoS (Denial of Service) attack, malicious nodes tend to prevent other authorized nodes from accessing the network’s data or services. In this paper, we propose a mechanism that is useful in the detection of DDoS attacks in a MANET by using Ad-hoc On-demand Distance Vector (AODV) routing protocol. In this paper, NS3 simulator is used for the simulation of the MANET and analyzing the DDoS attacks using AODV protocol. © 2016, International Journal of Pharmacy and Technology. All rights reserved.