Abstract: As an important component in the framework of the future network resource management, QoS routing is attracting more and more attention. In order to guarantee network quality of service, QoS routing algorithms try to find an optimum path that can provide sufficient resources to accommodate the performance requirements such as delay, jitter, bandwidth and loss rate required by applications. In terms of multiple metrics, most of the existing routing algorithms take bandwidth and propagation delay as routing metrics and find out the smallest propagation delay path among all widest paths and so on. Due to the complexity of network dynamic, the network state information is uncertain inherently, so it is necessary to research the influence of the uncertain information to QoS routing. A formalization description of QoS routing problems is given based on some uncertain parameters such as bandwith and delay. Then, the relevant process models and algorithms are presented. Finally, a multiple path mechanism is discussed to support adaptive QoS routing.