Among the marine organisms the cephalopod constitute a large amount and they are well known for their defense mechanisms by jetting escape movement by changing their colour. The main class of cephalopod include squid and cuttle fish. The ink sac of Loligo duvauceli generated as a byproduct during processing industry and it has low market value and cause environmental pollution. The present study was carried out to evaluate the antioxidant activity of Loligo duvauceli ink in methanol extract and partially purified form by catalase activity, hydroxyl radical scavenging activity and reducing power assay. The Ic 50 value also determined compared to methanol extract the partially purified form shows the higher Ic50 value, this revealed that the antioxidant activity was lower in partially purified form compared to methanol extract.