Abstract: In bottom water reservoir with thin interlayer and water layer underlying oil layer,fracture technical research controlled by fracture length in multi - injecting with setting diverting agent has been developed and studied.Through laboratory experiments,the type and combined pattern of the setting diverting agent have been sorted out.Finally,the operation parameters on multi - injecting the settling converting agent was optimized by using 3D software in Huaziping block.The oilfield application in 14 wells shows the purposes of oil increment and Water control have been achieved.