Abstract: Admission control algorithms have direct impact on the overall performance of advance reservation mechanisms in the distributed computing. Based on the advantages and disadvantages of existing flexible admission control algorithms, a fragmentable admission control algorithm for resource reservation is proposed. When the fixed resource reservation cannot be achieved, the algorithm allows reserving resources in fragments with the maximum fragment interval. And when there are slots whose remaining amount of resources is less than the requested amount in a fragment, it allows setting aside the minimum amount of resources. Experiments with other three kinds of extensible admission control algorithms (shorten the duration and increase the reserved bandwidth; reduce the reserved bandwidth and extend the duration; change the start time) show that the fragmentable admission control algorithm for resource reservation can effectively reduce the resource fragmentations, and obtain better performance in acceptance rate and effective resource utilization.