Abstract: In order to create a precise method for calculating the flexural bearing capacity of the new-type circular aluminium-concrete-steel double skin tubular （termed “ACSDST”）, in the report, based on the plastic stress distribution method （PSDM）, the theoretical derivation was performed to obtain a group of formulas for the flexural bearing capacity calculation, which can accurately account for the areas of different stress zones across the cross-section. A comparative analysis results of the obtained flexural bearing capacity of 168 ACSDST specimens and the finite element data demonstrated that the average error of the calculated values does not exceed 5.5%. Thus, these formulas can provide a good prediction for flexural bearing capacity of ACSDST sections, and which can provide the basis for their application and design.