Abstract: To solve the problem of deep profile control for stratum of high permeability and large pore passage and on the basis of advantages and shortcomings of ordinary chemical choking agent and the related choking mechanism,the FY blended rubber profile control agent,a new organic-inorganic composite choking agent,is manufactured in the laboratory and its performance is surveyed.The application result in well 5 -310 in Henan oilfield suggests that the profile control agent is characterized by high intensity,high choking intension and good choking effect and waterproof washing.