This paper presents a simulation framework for structured P2P (peer-to-peer) networks, which can be utilized in research of P2P networks. The framework provides foundational modules needed in structured P2P network simulation, presents a primitive set for structured P2P network simulation, and supports developing simulation environments for variety kinds of structured P2P network protocols and applications based on the framework. Furthermore, the framework concerns about the detailed model of underlying network, and it connects GTNetS simulation platform to accomplish packet-level simulation. The structure of the framework is described in detail and then applicability of the framework is validated by experiments.