Abstract: Provided is a cloud server system, the system comprising a plurality of multi-root input/output virtualized PCIE switches (MR-IOV Switches) that are interconnected each other. The cloud server system based on the MR-IOV PCIE Switch in the present invention can well meet the design requirements of the cloud servers very well, with a high performance-to-consumption ratio, strong overall service capability, low cost, low power consumption and high energy efficiency. I/O virtualization is realized architecture, thus maximally ensuring the performance of the server.