The vast majority of onshore oil fields have been developed by water injection and polymer injection for a long time， which leads to the development of large pore channels or high permeability bands，and the ineffective and inefficient circulation of injected water becomes more and more serious. Aiming at the technical problems of poor plugging effect of conventional profile control and water plugging agent，taking the reservoir and fluid characteristics of Western B oilfield as the research object，the basic performance，injection，plugging of starch graft copolymer gel（SGCG）was evaluated，and the stabilizing oil production and controlling water cut effect of SGCG under different factors was investigated. The results showed that the initial viscosity of SGCG was low，and the injection was good. However，the gel environment would affect seriously gelation. The larger the gelatin space， the higher the gelation strength. The sealing ability of SGCG to the high permeability core was stronger than that to the low permeability core，indicating that SGCG had less damage to the medium low permeability reservoir and had a selective sealing effect to a certain extent. In addition，it was found that the SGCG was not injected with PV，the more the better，there was a reasonable range. The highest recovery rate was obtained when injecting 0.1 PV SGCG. With the increase of gel dosage，the damage to the medium and low permeability increased，as a result，it was not conducive to the occurrence of fluid diversion. With the increase of displacement slug，the oil recovery increased gradually，however，the output-input ratio decreased gradually. The injection timing of SGCG also had an effect on increasing oil and decreasing water cut. The earlier the injection time was，the weaker the degree of heterogeneity was，the better the plugging effect was，and the higher the final recovery rate was.