A novel and facile approach to manipulate the morphology of Cu2+-ion-specific assembly of conjugated polymer by coordinative interaction at an oilwater two-phase interface is present. The application of increasing importance is the use of p-conjugated polymers as receptors, exploiting their ability to selectively form complexes, which can obviously change the optical properties in solution and induce the formation of varied solid nano/microstructures. By this method, microtubes are formed through self-rolling of a strained ionic bilayer film at the oil/water interface.