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Corrosion causes huge economic losses and waste of resources in the oil field,and it will bring serious safety hazard.In this paper,the problem of oxygen corrosion in the wellbore of water injection wells in the oilfield using simultaneous injection of water（produced water）and gas（nitrogen）is investigated.The corrosion prevention research is carried out from the aspects of pipe,corrosion inhibitor and coating,and the corrosion behavior is evaluated in high salinity simulated production water.In the screening of pipeline materials,the corrosion behavior of five materials N80,P110,P110S,J55 and L80 in high salinity corrosive media is mainly evaluated.The corrosion behavior of each metal material is evaluated by changing the experimental conditions,including temperature,oxygen partial pressure and simulated flow rate.After corrosion experiments,it is concluded that P110S is a cost-effective material and is recommended as the main pipeline material.In high salinity corrosive media,oxygen partial pressure and flow rate have a greater impact on corrosion rate.In the compounding of corrosion inhibitor,a compound anti-oxidation inhibitor which is mainly composed of molybdate and benzotriazole is compounded.The corrosion inhibitor has good solubility and stability in the high salinity simulated formation water,and is evaluated by the weight loss method,and the corrosion inhibitor has good corrosion inhibition effect.Under the experimental conditions of corrosion inhibitor concentration of 1 000ppm,reaction temperature of 120℃,total pressure of 12 MPa and oxygen partial pressure of 0.6 MPa,the selected P110S is used as the corrosion test piece,and the corrosion inhibition rate of the corrosion inhibitor is 66.98%.After 12 hours of pre-film treatment,corrosion inhibition rate is up to 86.64%.Characterized by SEM and EDS,the corrosion inhibitor does participate in the formation of the oxide film of the test piece,which acts to inhibit corrosion.For the screening research of coatings,after investigation and screening test,a special polyimide coating is screened.After evaluating the mechanical properties and chemical properties of the coating,it is found that the coating has superior performance and can meet the anti-corrosion requirements of severe corrosive environments in oil fields.The adhesion of the special polyimide coating is as high as 39.8MPa,and the wear rate is only 0.00168g/h,which is equivalent to the wear rate of zirconia and outstanding performance.The chemical reagent soaking corrosion test,salt spray test,mixed gas corrosion test,programmable temperature and humidity test and high salinity,high temperature and high pressure corrosion test show that the coating has excellent anti-corrosion performance,can adapt to the corrosion of harsh environment,and has good anti-corrosion effect.Combined with pipe and corrosion inhibitors,pipes and coatings to form an anti-corrosion solution,it can achieve a good anti-corrosion effect.