Abstract: QADPS (QoS-aware dynamic priority scheduling scheme), a new scheduling scheme for meeting the different QoS requirements of multimedia applications is introduced in this paper. When retrieving data from the storage systems, multimedia applications need the guarantee of QoS. The fraction of requests whose response time exceeds a specific delay limit must be below a certain proportion. Different multimedia applications may have different QoS requirements in the mixed multimedia workloads. Based on the history of a multimedia application receiving service, its QoS failed-distance can be calculated. The basic idea of QADPS is to assign higher priority to the multimedia applications that have shorter failed-distance. Using this scheme, the requests of the multimedia applications with stricter QoS requirements can achieve more chances of service applied by the storage systems. The effectiveness of this approach is evaluated through simulation. Compared with the conventional scheme, QADPS substantially increases the number of the concurrent multimedia applications.