In the present study, submicron ion-exchange fibers (IEFs) of polystyrene (PS) and its blends with styrene-butadiene-styrene block copolymer (SBS) were prepared by electrospinning and postsulfonating modification. Scanning electron microscopy (SEM) images showed that the diameters of the fibers enlarged significantly after treatment and the surfaces become rougher. Mechanical properties analysis showed that the electrospun fibers (EF) and the IEFs from PS/SBS blend fabrics possessed better mechanical performances than those from pure PS. The ion-exchange capacity (IEC) of 4.35 mmol/g and and copper ions (Cu2+) adsorption value of 3.08 mmol/g for IEFs from PS/SBS blends were both higher than that of IEFs from pure PS and the conventional IEFs produced by coating or grafting fibrous substrates with functionalized resins or monomers. Dynamic adsorption experiments were made to test the behavior of adsorption for Cu2+. The results of dynamic adsorption experiments with Cu2+ showed that the IEFs from PS/SBS would quickly purify 3000 ml waste water containing Cu2+ (100 mg/L), and the removal rate for Cu2+ reached 96.5% even at the flow rate of 12 ml/min. The study provided an absorbent with a high dynamic adsorption capacity for removing Cu2+ from waste water.