The invention relates to a node cooperation method and system in a peer-to-peer network streaming media system. The node cooperation method is used for reducing total load of a server in a network on the basis of nodes in a peer-to-peer network and a server mode network. The node cooperation method comprises the following steps of: 1, generating virtual nodes by the nodes in the peer-to-peer network; and 2, scheduling data on the basis of services of the generated virtual nodes to the nodes in the network, wherein the scheduling method comprises the procedures of during scheduling the data, if data packets required by the nodes can not return from adjacent nodes, requesting for the virtual nodes, and if the virtual nodes do not have the data packets, requesting the data to the server, wherein the virtual nodes have additional service capacity under the condition that the nodes in the network meet the self working demands, and meanwhile, the additional service capacity is virtualized into a new node to be added in the network for cooperation, and the generated new node is named as a virtual node.