Abstract：Casing damage during water injection well blowout is general in petroleum engineering，and it is difficult to resolve in many oil fields of China. In order to study the mechanism of the problem，fluid-solid coupled model is set up. According to the fundamental equations and boundary conditions，the ANSYS function of temperature field analysis is similar to that of seepage flow field. Based on the similarity of the formulas between the temperature field and fluid field，the coupling element between temperature and stress—Solid 5 Module in ANSYS program is employed to analyze the fluid and pressure coupling in the strata-casing-cement system. The method can solve the seepage flow problem of complex boundaries and mediums. By means of numerical simulation，the fluid field in the strata and the relation between casing extrusion stress and pressure releasing rate are studied. The simulation results show that，the bigger permeability，the bigger extrusion pressure of casing damage as the same relief discharge.
