Double skin composite walls (DSCWs) consist of two skins of profiled steel sheeting and in-fill of concrete. DSCWs are proposed to act as axial and lateral load resisting elements in buildings. This research concentrates on the structural performance of DSCWs made of high performance concretes (HPCs) subjected to elevated temperatures of 800oC maintained for steady state duration of two hours. Performance of DSCWs subjected to elevated temperatures is evaluated in terms of physical changes, residual axial load capacity/stiffness, axial load-deformation response, ductility, strain characteristics, steel-concrete interaction, and overall failure modes. Analytical models for the residual axial load capacity of DSCWs are developed based on experimental results. The recommendations of this research will be useful for the development of guidelines for the post-fire axial strength/ductility/stiffness of DSCWs and will aid in the development of fire protection measures.