In order to meet the strength，gelling time and gel breaking performance requirements of the gel plugging system for high pressure water injection wells under pressure operation，a temperature-resistant and salt-resistant gel plugging system was developed. This system utilized acrylamide（AM）/2-acrylamido-2-methylpropanesulfonic acid（AMPS）as a binary polymer system and trimethylol compound（Smel30）as crosslinking agent. The effects of temperature，inorganic salt，simulated oil content，and shear time on gelling time and gel strength of the system were investigated. Additionally，the influence of sodium persulfate on gel breaking effect of the system was studied. The results showed that when the temperature increased from 40 ℃ to 100 ℃，the gelling time of the system decreased from 23.5 hours to 2.0 hours，while the gel strength increased from 39.4 Pa to 88.6 Pa. Inorganic salts could reduce the distance between polymer chains，which led to shorter gelation time and a slight increase in gel strength. Three inorganic salts were arranged according to the effects on gelling time and gel strength of the system in following order：NaCl < MgCl₂ < CaCl₂. The gel system exhibited strong resistance to oil stains and shear forces. The addition of 1%—10% simulated oil increased the gelation time from 8 hours to 15 hours，with minimal change in gel strength. After shearing at 60 ℃ and 500 r/min for 60 minutes，the gelling time increased from 7 hours to 17 hours，while the gel strength remained 81%. The gel system displayed good thermal stability. There was no significant dehydration after aging at 60 ℃ for 15 days，and then the gel strength remained at 67 Pa. Sodium persulfate was an effective and cost-efficient gel breaker. After adding 30%（mass fraction）sodium persulfate with dosage of 30% volume fraction to the gel system，the gel breaking time at 60 ℃ was 20 hours，and then the apparent viscosity of the residual liquid was 64.4 mPa·s. The gel breaking residual liquid could be easily displaced to the ground using gas or water， meeting on-site construction requirement.