Cryogenic air separation is currently the most widely used but energy-intensive technology for producing large quantities of oxygen and nitrogen, where cryogenic distillation consumes about 75% of the whole air separation field; however, its thermodynamic efficiency is very low. A novel structure of a full tower ideal internal thermally coupled air separation column (ITCASC) is therefore first proposed in this paper. A rigorous mathematic :model and parameter analysis are then presented. Research results show that the proposed ITCASC process can yield high-purity products of both oxygen and nitrogen simultaneously and especially has a strong driving force of heat transfer, which reveals the larger energy-saving potential in the ITCASC process. Furthermore, an optimization model of the operation parameters is presented, where, both the actual energy-saving potential and the ideal energy-saving potential of ITCASC are investigated. Comparative studies against the conventional cryogenic air separation column (CASC) are carried out in detail. Research:results:show that the proposed ITCASC Process has a larger extraction rate and better energy efficiency, where the nitrogen extraction rate increases 177.94% and the unit energy consumption decreases 40% compared to the CASC process with the same product purity requirements, revealing the advantages and promising application prospect of the proposed ITCASC process.