The rapid need of Information Technology and that too wireless usage demands a great deal of security in order to keep all the data sources and equipment’s secure. So we need a secured network to secure all these. But Secured data communication over Internet and any other network is always under threat of intrusions and misuses. So Intrusion Detection System has become necessary in terms of network security. There are various approaches that have been used before in Intrusion Detection Systems but all of the approaches have some types of flaws in it. So the scope of betterment is always there. In this paper we proposed an Intrusion Detection System (IDS) by applying Genetic Algorithm (GA) to effectively detect the network intrusions. Various Parameters and evolution processes for GA are discussed in detail and implemented so that to overcome the flaws that was present in previous Intrusion Detection Systems.