Abstract: Resource management is a key problem in metacomputing systems and resource co-allocation must be resolved effectively for large-scale metacomputing applications. In this paper, an extensible hierarchical resource management model is proposed, which provides a uniform interface for heterogeneous resources through the interaction between the core resource managers and local schedulers based on the utilization of existing batch scheduling systems. A site-based hierarchical management mechanism is also proposed for resource co-allocation. It can distribute the requests of the application to relatively tight resource sets, which will not only decrease the total communication overheads of the applications but also provide advance reservation services for computing.