Performance Investigation of Reactive AODV and Hybrid GRP Routing Protocols under Influence of IEEE 802.11n MANET In modern technology era, the endeavor of MANET is to provide proficient wireless communication by adopting adhoc routing functionality in mobile nodes. The MANET nodes result in frequent networktopology changes, making routing a challenging task. In past, Reactive routing approaches are used as a popular technique that provides scalable solution to relatively large MANET networks, where HybridMANET routing algorithms are introduced comprises of both reactive and proactive routing properties. This work is an attempt towards a comprehensive performance evaluation of commonly used reactive AODV protocol with hybrid GRP routing algorithm under varying node density conditions in terms of QoS using OPNET Modeler 17.5 Academic.