资源发现是网格计算中相当关键的技术。随着网格技术的不断进步，资源数量不断增加,如何在庞大的网格环境中准确高效地发现用户所需资源，成了网格技术必须解决的问题。本文对现有的两种网格资源发现模型进行了简要的分析,为解决存在的问题,提出了基于移动Agent的多层次结构的资源发现模型，利用DHT缓存和路由技术覆盖网络，采用LDAP目录服务技术、移动Agent技术传输信息、基于Web语义的本体描述资源信息，详细介绍了它的总体框架、工作机制，最后给出了性能分析。

Resource discovery is a relatively important method in grid. Along with the development of grid technology，the increase of the number of resources, it is a problem we must resolve that how to accurately and efficiently discover resources to meet the users’ need. This paper briefly analyzes two existing models of grid resource discovery to solve the existing problems,advances a mutilevel model based on mobile agents to discover grid resources, uses the DHT cache and route technology to cover networks, adopts the LDAP directory service and mobile agents to transmit information，and describes the resources by ontology based on Web semantics. The overall framework and working mechanism are  introduced in detail and an evaluation is given.