This paper proposes an Agent Community based Peer-toPeer information retrieval method called ACP2P method, which uses agent communities to manage and look up information related to users. An agent works as a delegate of its user and searches for information that the user wants by communicating with other agents. The communication between agents is carried out in a peer-topeer computing architecture. In order to retrieve information related to a user query, an agent uses a content file, which consists of retrieved documents, and two histories : a query/retrieved document history(Q/RDH) and a query/sender agent history(Q/SAH). We implemented this method with Multi-Agents Kodama[1], and conducted preliminary experiments to test the hypothesis. The empirical results showed that the method was much more efficient than a naive method employing ’multicast’ techniques only to look up a target agent.