In this paper, Cu/magnetic chitosan has been synthesized and used as a new green nanocatalyst for highly efficient synthesis of 2,4,6-triaryl pyridines via C–N bond cleavage of benzylamines under aerobic oxidation at 90 °C. The chemical and structural properties of the synthesized catalyst were determined by scanning electron microscopy, energy-dispersive X-ray, X-ray powder diffraction, thermogravimetric analysis and flame atomic absorption spectroscopies. It is found that the catalyst can be easily separated from the reaction mixture by an external magnetic field and recycled several times without a significant loss in activity.