Abstract: Mechanical analysis of FRP-concrete-steel hybrid double-skin tubular columns is presented in plane strain conditions. A theoretical model of stress-strain relationship is proposed with the consideration of Elasto-plasticity of concrete and steel tube. The specimens are considered to be damaged when the ultimate state of FRP tube is achieved. The calculation results are in good agreement with experimental results. Based on the theoretical model, parametric analysis is presented. The results indicate that the stress-strain curves are affected by FRP tube type, void radio and concrete strength. However, diameter-to-thickness ratio and strength of steel tube have little influence on the stress-strain curves.