Eclipta alba (Asteraceae) is used traditionally in ayurvedic system of medicine in India for the treatment of liver diseases and also used as a liver tonic. In vitro antioxidant activity of hydro-alcoholic extract of Eclipta alba was evaluated by studying superoxide radical scavenging activity, hydroxyl radical scavenging activity, nitrous oxide radical scavenging activity, 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity, reducing ability and Fe+2 chelating ability using standard procedure. Identification and quantification of the wedelolactone, one of the active constituents of the Eclipta alba plant extract, was carried out by HPLC analysis. Result of the present study indicates that the Eclipta alba extract shows high amount of phenolics, flavonoids, tannins and ascorbic acid contents. Hydro-alcoholic extract of Eclipta alba effectively scavenged free radicals at all different concentrations and showed potent antioxidant potency and effects were in a dose-dependent manner. Eclipta alba extract possess potent antioxidative properties.