Abstract: To achieve the experimental scheme study of the AP containment, H2TS method was used to carry out the system-level scaling and the result showed the prominent distortion of area-volume ratio. Based on the basic criteria of volume-power ratio, the Bottom-Up scaling approach was used to analyze the interdependent relations for the coupled heat transfer on the containment wall. The П group on AP containment heat removal was then obtained. Thermal conduction on the containment wall was taken as an example for scaling analyses. Schemes were then given to offset the scaling distortions. Relations of structure dimensions by scaling-down were finally listed. The current scaling technique could be applicable to the scaling of large scale and large space thermal-hydraulic phenomena.