A green approach for efficient and rapid synthesis of biologically active substituted Hantzsch 1,4-dihydropyridine and polyhydroquinoline derivatives using magnetic Fe3O4 nanoparticles (Fe3O4 MNPs) as a recyclable catalyst under solvent-free conditions was reported. The catalyst was characterized by FT-IR, XRD, and TEM analysis. Compared to the classical reactions, this method consistently has the advantages of short reaction times, little catalyst loading, high yields, easy magnetic separation and reusability of the catalyst. (C) 2013 Elsevier B.V. All rights reserved.