Abstract: The platform-specific code in the distributed real-time systems (DRTS) is a main contributer to the complexity and cost of application software development. It reduces the maintainability and transplantability, but is not capable of ensuring the performance of real-time tasks. In this paper, an adaptive resource management middleware (ARMM) service based on the real-time CORBA and a QoS (quality of service) adaptation mechanism based on the optimal reward are proposed. A set of QoS APIs that is orient to real-time tasks is provided. The user-level resource management and software development are separated from the hardware platform by resource self-profiling and QoS adaptation. Thus the cost and complexity of application software development of DRTS is reduced, and the resource allocation under unpredictable environment can be dynamically optimized according to the outside variation.