This work was focused on the synthesis and characterization of iron nanoparticle loaded sawdust carbon(Fe/SC) by low cost green synthesis approach and its application for catalytic pyrolysis of heavy oil. Fourier transforminfrared (FT-IR), X-ray diffraction (XRD), scanning electron microscope (SEM), energy dispersive spectroscopy (EDS),transmission electron microscope (TEM), X-ray photoelectron spectroscopy (XPS) and inductively coupled plasmaoptical emission spectrometer (ICP-OES) methods were used to analyze the catalyst of Fe/SC. The properties of heavyoil before and after reaction were characterized by SARA analysis, FT-IR, gas chromatography-mass spectrometry (GCMS)and thermogravimetric analysis (TGA). The experimental results showed that after pyrolytic reaction at 350 oC for30 min with 0.1 wt% catalyst, the viscosity of heavy oil may decrease by 80.81% with a net efficiency of catalyst of20.68%. The catalyst of Fe/SC is promising, low cost, high efficiency, highly stable and eco-friendly for catalytic upgradingand viscosity reduction of heavy oil.