The resin poly(acrylamide-co-methacrylic acid) P(AAm-co-MA) by radical polymerization was synthesized and its metal ion binding was studied using the batch and column equilibrium procedures for: Cd(II), Zn(II), Pb(II), Hg(II), Al(III), and Cr(III). Experiments were carried out at different pH, metal ion concentration, temperature, and contact time. The resin's retention behavior was influenced by the pH. The highest retention 91% (0.248 mmol/g, 6.7 mg/g) was achieved at pH 5 for Al(III), and 87% (0.265 mmol/g, 54.9 mg/g) for Pb(II). For Hg(II), the yield was 85% (0.318 mmol/g, 63.7 mg/g) at pH 2. The metal-ion retention properties were dependent on the polymer/metal ion ratio. Under competitive conditions of Pb(II), Hg(II), and Al(III), the resin showed a higher retention of Hg(II), allowing the selective separation of this metal.