Antioxidants are emerging as potential prophylactic and therapeutic agents which scavenge free radicals and prevent the damage caused by them. The quinones and their derivatives containing hydroxyl group exhibits wide range of pharmacological activities such as antioxidant, antibacterial, antiviral, anticancer, antimalarial and antifungal activities. In particular the antioxidant and anticancer behaviors of these compounds continue to draw attention of researchers. In the present communication, three natural naphthoquinones 1-3 isolated from nutshells of Juglans regia Linn., and five synthetic naphthofuran derivatives 4-8 obtained by structural modification of natural naphthoquinones. The structures of these compounds were characterized by 1HNMR, 13CNMR, IR and Mass spectral studies. In vitro cytotoxicity using human hepatocellular liver carcinoma cell line (HepG2) and antioxidant study using ABTS and DPPH were carried out for these compounds. The naphthofurans 6, 7 and 8 displayed almost equivalent scavenging activity on DPPH assay and higher activity on ABTS assay relative to ascorbic acid. On the other hand naphthoquinones 1 and 3 showed lesser antioxidant activity but higher cytotoxic activity than naphthofurans except 5 which showed excellent cytotoxic activity.