The process in which the nanofiber membrane is used to remove heavy metal ions and separation of oil-water solution is analyzed. Herein, smooth structures are induced by rGO-g-PAO sheets, which could be attributed to the strong interaction between P(AN-MA) and rGO-g-PAO. It is rewarding to note that the P(AN-MA)/rGO-g-PAO nanofiber membrane would exhibit superhydrophilic traits in the air and ultra-low oil-adhesive traits underwater when the concentration of P(AN-MA) and PAO is 13 wt.% and 0.3 wt.%, respectively. The amidoxime (-C(NH₂) NOH) groups on the membrane surface can efficiently adsorb copper (Cu(II)) (1.65 mmol/g) and chromium (Cr(VI)) (4.70 mmol/g) ions in the waste water. Meanwhile, the P(AN-MA)/rGO-g-PAO nanofiber membrane exhibits ultrahigh flux (~6150 LMH), satisfying rejection rate (~97%) and outstanding flux recovery ratio (~99%) in separating oil water emulsion.