Centralized cluster system is widely used by many web sites to increase service availability and balancing workload among multiple servers. In order to reduce the possibility which balancer becomes performance bottleneck in clusters, a dynamic adaptive weighted load-balanced algorithm is presented in this paper. The objective of the algorithm is that every working server sends a corresponding ask signals at different rates to balancer based on the discrete uniform distribution principle and the balancer assigning user requests according to an ask queue which consists of these signals and achieves the dynamic negative feedback on workload. Experiment results show that the algorithm is better than the static algorithm, as compared with the dynamic algorithm, it can also reduce the burden on load balancer.