Abstract: Drag reduction and throughput increase mechanism for oil and gas pipelines are described based on flow law of fluid in pipeline. In allusion to the issues about large frictional drag of flow and narrow suitable transportation scape of throughput existed in oil and gas pipelining, relative technologies to improve transportability of oil and gas pipelines are investigated and discussed.It is considered that frictional drag and energy consumption of pipeline can be remarkably decreased by means of reducing dynamical viscosity of fluid and additional stress of turbulance, which can raise operating flexibility and transportability of pipelines and ensure safe and economic running of pipelines for drag reduction and throughput increase. On account of oil pipeline system, application effectiveness of different drag reduction and throughput increase techniques as well as their suitable scopes are analyzed, and some new techniques with application prospect are put forward.