The invention provides a flexible data transmission system based on an SINET (Smart Identifier NETwork), comprising a resource management unit and a network assembly unit, wherein the resource management unit comprises a network state sensing module, a network state measuring module and a flexible transmission module, the flexible transmission module is used for calculating K shortest transmissionpaths and determining the optimal transmission path based on a network topology state and a network resource update state obtained by the network state sensing module as well as a network state linkmaximum available bandwidth and delay information measured by the network state measuring module. Through adoption of the flexible data transmission system of the invention, under centralized and unified control of an SINET control plane, the network state and the network assembly behavior are sensed, in combination with parameters such as routing hops, residual bandwidth and link delay, the optimal transmission path can be determined to achieve dynamic adaption and transmission of service resources, and data transmission reliability, network throughput, resource utilization rate are improved,link load balancing is achieved, so as to make up for the deficiency of a shortest routing method.