Through systematical research and complex analysis of how the main safety facts affect flow characteristics of oil & gas pipeline, oil & gas pipeline flow assurance is a series of technology which aims to ensure the safe operation of pipeline. The history, current research and future trend of oil & gas pipeline flow assurance are discussed. It is presented that this research field contains four main topics, which include oil rheological research and application, oil & gas pipeline flow improver research, flow characteristics of batch transportation of oil & product oil. The future focus of this research field is presented.