A dual-mode dividing wall column capable of mode switching between a dividing wall column operating mode and a conventional column operating mode, and a distillation method using the dual-mode dividing wall column, wherein when compared to the existing conventional column, the invention can reduce device costs and energy and improve productivity is described. Furthermore, since a mutual conversion between a dividing wall column operating mode and a conventional column operating mode is enabled without shutting down a process, an economic loss which can occur during shutdown caused by the malfunction of a device can be prevented.