The present invention provides a cloud computing based P2P streaming media server cluster deploying method, in which the bandwidth requirement of a P2P streaming media live broadcast system with delay protection can be predicted, and a virtual streaming media server cluster is built on a cloud platform DCN network. Specially, a method for predicting the bandwidth requirement of the P2P streaming media live broadcast system with delay protection is based on data package delay protection, and has parameters of delay protection time, and push-pull percentage and uplink bandwidth available rate of a P2P topology network, thereby building a bandwidth requirement model for the P2P streaming media live broadcast system for bandwidth prediction. A method for building the P2P streaming media server cluster on the cloud platform DCN network is based on the bandwidth requirement of the P2P streaming media live broadcast system with delay protection, and builds a logical structure for the P2P streaming media server cluster. The P2P streaming media server cluster is deployed on a cloud platform by constructing a deployment matrix of the P2P streaming media server cluster.