A new magnetic heterogeneous copper catalyst was prepared by immobilization of copper ions onto a cross-linked polymeric nanocomposite composed of starch grafted polyacrylamide and functionalized Fe₃O₄ magnetic nanoparticles. The resulting support was loaded with large amounts of copper ions (1.6 mmol g⁻¹). The prepared catalyst is highly active in Huisgen 1,3-dipolar cycloaddition reactions of different azides and alkynes at low catalyst amounts. Various corresponding 1,2,3-triazoles were produced with high yields in mild conditions. The catalyst was easily recovered and reused for ten cycles of reaction and no significant loss of catalytic activity was observed.