Vehicular networks are increasingly gaining popularity among researchers for their potential to enable diverse applications associated with road traffic safety, infotainment and road transportation management. In this paper we present a QoS-based routing protocol named VanetQoS which purpose is to accommodate real-time and multimedia applications with specific quality of service (QoS) requirements. Therefore, routing such applications data over a vehicular ad hoc networks (VANET) consists of selecting the most appropriate route that complies with required QoS. Our proposed protocol uses an algorithm which is based in multi-constraint path (MCP) problem, and which essential task is the selection of the best path among several available ones, by using and evaluating a composite formula expressed in terms of the QoS requirements such as required bandwidth, maximum delay and jitter, and minimum link expiry time. In this paper we present the architecture and design of our protocol, and provide performance results, which show the benefits of using our scheme for the purpose of routing multimedia traffic in VANET. The performance evaluation is achieved through simulation experiments using OMNET++ simulator.