Abstract: As Huzhuang oilfield has entered high water - cut stage,the conventional profile control agent could not meet the production demands.Field testing and applied researches of expanded profile control agent have been carried out due to strong reservoir heterogeneity in Huzhuang oilfield.The results show the technology has solved the problems occurred to conventional profile agent such as poor injection effect and poor driving performance,alleviated the interlayer interference and achieved obvious effect of increased oil and decreased water.In one word,the expanded profile control agent provides a new approach for improving oil recovery at high water - cut stage.