Using zwitterionic monomer (ZM), cassava starch (CSt) and polyvinyl alcohol (PVA) as main raw materials,a ZM graft copolymerized CSt-PVA interpenetrating network composite gel (ZPG2) was prepared through a freezing cross-linking method with a one-pot process. ZPG2 was characterized by Fourier infrared spectrometer(FTIR), Thermogravimetric analyzer(TGA), Polarized light microscopy (POM), Scanning electron microscope and Energy dispersive spectrometer (SEM-EDS). Static adsorption effects of ZPG2 on Cu2+ was evaluated. The results showed that ZPG2 had good thermal stability below 300 ℃. The presence of ZM produced an anti-polyelectrolyte effect and a chemical coordination effect, which could increase gel adsorption capacity significantly. Saturated adsorption amount could be as much as 199 mg/g when adsorption temperature was 25℃, ZPG2 dosage was 0.1g, Cu2+ concentration was 2×103 mg/L, and the solution volume was 100mL. The data of adsorption was in accord with Langmuir isotherm adsorption model and pseudo-second-order kinetic model.