Abstract: With the improvement of concrete strength, its utilization efficiency is reduced due to the strength reduction caused by the brittleness of concrete. However, existing numerical analysis models of concrete-filled double-skin steel tubular (CFDST) columns did not consider the reduction effect of concrete strength, which leads to large discreteness in performance analysis of CFDST columns filled with higher strength concrete, thus affecting the actual engineering design. In order to analyze the mechanical properties of CFDST columns more effectively and accurately, the fiber element analysis model of axially loaded CFDST short columns considering the effective concrete strength was established. Meanwhile, a strength reduction coefficient considering the effect of concrete brittleness on the concrete strength was introduced into this model. Further, by comparing the author’s previous test results and collected test data, as well as the existing fiber element analysis models, it was found that the proposed fiber element analysis model has a higher prediction accuracy. Based on the verified fiber element analysis model, the effects of column parameters on the axial compression performance of CFDST columns were studied. The results show that: the concrete strength, hollow ratio, yield strength of outer steel tube and diameter-to-thickness ratio of outer (inner) steel tube affect the carrying capacity and ductility of CFDST columns, while the yield strength of inner steel tube only affects the carrying capacity of CFDST columns and has little effect on the column’s ductility. Finally, based on the experimental and numerical results, a formula for calculating the axial carrying capacity of CFDST columns was proposed, which is in good agreement with the experimental and numerical results.