Using ABAQUS software,the finite element calculation model of square piers with tenon-groutingsleeve mixed connection was put forward by selecting material constitutive model and element type reasonably ,dividing mesh and establishing boundary condition. The failure mode of concrete and the ultimate bearing ca-pacity of concrete under axial load were compared with the test results, and the accuracy of finite element cal-culation was verified,the stress state of internal steel bar,steel pipe and grout sleeve was analyzed as thepressure increased.On this basis,taking the design parameters of CFST tenon ( concrete-filled steel tube ten-on ) as the variables,the influence of the variables on the axial compression performance of the short pie of tenon-grouting sleeve hybrid connection was further studied,the results showed that the proposed finite ele-ment model could simulate the axial compression process of the square piers with tenon-grouting sleeve joint ,the mean and variance of the ultimate bearing capacity calculated by finite element method and the test results were 1.036 and 0.023,respectively. Increasing the length and diameter of CFST tenon steel pipe could obvi-ously increase the ultimate bearing capacity of the mortise-grouting sleeve connection bridge pier,the changeof the thickness of CFST tenon steel tube had an increasing and decreasing trend for the ultimate bearing ca-pacity of mortise-tenon-grout sleeve bridge pier, but it has little effect on the length and diameter of steel tube.Iln this studly , a simplified formula for calculating the axial bearing capacity of square piers with mortise-tenon-grouted sleeve connection was presented. The calculated results were slightly lower than the results of tests andfinite element analysis , and the average error between the calculated results and the experimental results was9.01% , the error was 4.05% , and the error was small. It could be used to calculate the axial bearing capaci-ty of this type of pier.