The invention provides an internode collaboration method in a P2P system, which comprises the following steps: 1) leading nodes to carry out periodical monitoring on data demand situation and servicestate of the nodes, and judging whether collaboration with other nodes needs to be requested or not; 2) forecasting the current service capability of each node according to preserved historical records, simultaneously periodically monitoring the service state of each node, and determining whether each node has surplus service capability or not; and 3) sending a request after the node determines that the collaboration with other nodes is needed, seeking the nodes which can participate in the collaboration, if the surplus service capability does not exist or the surplus service capability is lower than a preset threshold after other nodes receive the collaboration request, ignoring the request, otherwise, participating in the internode collaboration, obtaining the data from the nodes owned by hot data, and meeting the demands of other nodes on the hot data. The method makes full use of the surplus service capability of the nodes to meet the data demands of the hot data, realizes the loadbalance of a plurality of nodes and improves the availability and the robustness of a whole system.