The present disclosure belongs to the field of data transmission, and provides method, device and system for downloading data blocks of resource files. The method includes: when a target peer needs to download a target resource file, the target peer notifies a tracker server of a file size and a URL of the target resource; the tracker server forwards the file size and the URL to super peers preset in a P2P network to notify the super peers to prepare data blocks of the target resource file meeting the file size and the URL; after the super peer is ready, the tracker server recommends the super peer to the target peer in a form of a peer list; furthermore, the target peer downloads the data blocks of the target resource file from the super peer. With technical solutions of the present disclosure, validity of the resource file downloaded by the target peer may be guaranteed.