The antioxidant activities of twelve naphthalene compounds containing (E)-1-((3-iodophenylimino)methyl) naphthalen2-ol(NAPH1), (E)-1-((3-bromophenylimino) methyl) naphthalen-2-ol (NAPH2), E)-1-((4-bromo-2-(trifluoromethoxy)phenylimino) methyl) naphthalen-2-ol, (E)-1-((4-bromo-2-(trifluoromethoxy) phenylimino) methyl)naphthalen-2-ol(NAPH3), (E)-1-((2-methoxy-5-(trifluoromethyl) phenylimino) methyl) naphthalen-2-ol (NAPH4), (E)-1-((naphthalen-2-ylimino) methyl) naphthalen-2-ol (NAPH5), (E)-1-((2-bromo-3-methylphenylimino) methyl) naphthalen-2-ol (NAPH6),(E)-N-((2-ethoxynaphthalen-1-yl)methylene)-3-methylaniline (NAPH7), (E)-4-ethoxy-N-((2-ethoxynaphthalen-1-yl)methylene) aniline (NAPH8), (E)-N-((2-ethoxynaphthalen-1-yl) methylene) naphthalen-1-amine (NAPH9), (E)-1-(2,5-difluorophenyl)-N-((2-ethoxynaphthalen-1-yl) methylene) methanamine (NAPH10), (E)-N-((2-ethoxynaphthalen-1-yl)methylene)-4-fluoroaniline (NAPH11), (E)-N-((2-ethoxynaphthalen-1-yl)methylene)-2-ethylaniline (NAPH12) wereinvestigated in vitro by antioxidant activity (phosphomolybdenum assay), reducing power, H2O2 scavenging activity,metal chelating effects and lipid peroxidation. Scavenging activities of the naphthalen compounds were tested against1,1-diphenyl-2-picrylhydrazyl, hydroxyl and superoxide anion radicals. Most of them are potent antioxidant, radicalsuperoxide anion scavengers and in vitro inhibition of lipid peroxidation. The compounds; NAPH5, NAPH10 and NAPH12were found to exhibit promising antioxidant profiles at 10 and 50 mM concentrations. Among these, NAPH5 at higherconcentration was the most active compound in inhibiting lipid peroxidation as shown in the homogenates of kidney,heart and spleen. The presented results validate that NAPH5, NAPH10 and NAPH12 can be possessed as a source ofantioxidant potential and a rich source of synthetic antioxidant for medicinal or foods.