The invention discloses a mobile P2P network data prefetching method based on interest-relevance. The method comprises that S100) unique overlay network identifications are distributed for all nodes in the P2P network; S200) the network nodes are gathered into clusters according to the physical positions, and one super node is selected from each cluster; S300) the super node calculates and analyzes historical access records of common nodes in the cluster, and calculates data prefetching values according to the interest-relevance, the support degree, the confidence, the data size, the path length and the like; and S400) the super node makes the data prefetching decision, and prefetches nodes of high prefetching values to nodes of high capability in the cluster. The method can be used to improve the buffering hit rate of the mobile P2P network more effectively, reduce time delay of user access and improve the network service quality.