The synthesis and characterization of the water-soluble poly(N-acetyl-alpha -acrylic acid) by radical polymerization were carried out. The polymer was characterized by Fourier Transform Infrared (FT-IR), H-1 NMR and C-13 NMR spectroscopies, and thermogravimetric analysis (TGA). The metal ion binding properties for the metals Cu(II), Co(II), Ni(II), Cd(II), Zn(II), Pb(II), Hg(II), Cr(III) in the aqueous phase were studied using the liquid-phase polymer-based retention technique. The metal ion interactions with the hydrophilic polymer were determined as a function of pH and of th filtration factor. The polychelatogen showed a high affinity for metal ions and higher selectivity for Cr(III) at pH = 3.