Reactive Powder Concrete (RPC) is a kind of cement-based composite which has ultra-high strength, high ductility and durability. RPC has great fragility, bad ductility and bursting fragility destruction subjected to high or complicated stress. The fragility performance of RPC will be improved when RPC is cast in steel tubes. The behavior of axially loaded RPC-filled steel tube circular stub columns is presented in this discussion according to the experiment and finite element analysis. An accurate finite element model was developed to carry out the analysis. Accurate nonlinear material models for confined concrete and steel tubes were used. The results obtained from the finite element analysis were verified against experimental results.