Abstract: Huatugou oilfield is a typical complex fault block and has the characteristics of long interval,thin inter-bedded,serious heterogeneity,complex oil-water relationship,poor injection-production corresponding difference,waterflooding monolayer onrushing,quickly dropped formation pressure and higher production decline rate.In order to improve the oilfield water flooding development effect,on the basis of fine reservoir description,through fine injectionproduction adjustment measures,such as by improving water quality,perfecting well pattern,strata subdivision,separate water injection,and remaining oil potential,the water drive control degree and the reservoir producing degree have been improved,the formation pressure is going up steadily,and the natural decline decreases.Therefore,the comprehensive development effect has been improved significantly.