A concept of target ions removal from wastewater by using a potential-responsive film with ions-selectively capture effect was proposed. A poly(2,2′-dithiodianiline) (poly(DTDA)) film with three-dimensional (3D) porous structure was fabricated based on this concept to remove copper ions from wastewater. By modulating the applied potential on the film, disulfide/dithiolate (-S-S−/−S- −S-) of poly(DTDA) acted as the claw to selectively capture and release the copper ions. The mechanism of the potential-responsive ions-selectively capture effect on the capture/release process was analyzed by using X-ray photoelectron spectra (XPS), Raman spectra and density functional theory (DFT) calculations. Furthermore, the poly(DTDA) film exhibited high selectivity to copper ions in two kinds of real industrial wastewater and maintained excellent release efficiency of copper ions. Finally, the capture capacity retention and release efficiency remained more than 0.8 and 90% after 10 consecutive cycles, respectively. Such a poly(DTDA) film could be a potential material for the removal and recovery of copper ions from wastewater in industrial processes and the proposed concept is expected to be also applied for the removal of other target ions by developing special materials.