Abstract: In view of the high temperature and high salinity of Gasikule E₃¹ reservoir, the reservoir heterogeneity is strong and the remaining oil is dispersed, and the water channeling is serious during water flooding development, resulting in low efficiency of water flooding. For such a high-temperature and high-salinity reservoir, the conventional chemical profile control plugging agent is prone to breakage and degradation, and it is difficult to play a significant role. The optimal formulation of the profile control agent in the formation with the average reservoir temperature of 126 ℃ and the average formation water salinity of 16.5×10⁴ mg/L was developed by the experiment: crude konjak powder (concentration 5.0 g/L) + suspending agent (concentration of 700-1 000 mg/L) + cross-linking agent (volume fraction 1.0%-1.2%) + oxygen scavenger (concentration 100-200 mg/L). The experimental results show that the profile control agent was aging 30 days under the conditions of high temperature(126 ℃) high salt (mineralization degree of 16.5×10⁴ mg/L), then the plugging agent system of micro-dehydration has no broken plastic phenomenon with good temperature resistance and salt resistance.