A wireless ad-hoc network is a self-organized wireless network without fixed or backbone infrastructure. All nodes have routing capability and use peer-to-peer packet transmission or forward packets to other node using multi hop communication. Now-a-days Mobile Ad-hoc NETworks are being used for different applications and traffics, so it require Quality of Service (QoS) support in routing protocol. In this paper, a modified QoS routing protocol using directional antenna has been proposed. High and normal priority can be assigned based on type of traffic. All the nodes in the path used by high priority flow are reserved as high priority flow for that flow and normal priority flow will avoid the paths used by high priority flows.