Merremia tridentata (L.) Hallier f. is a member of Convolvulaceae family. This plant is used in the treatment of various ailments in folk medicine. In the present study, total phenolic contents and antioxidative properties of aerial parts and roots of M. tridentata were examined in different solvent extracts. The antioxidant activities were evaluated by measuring the ability of the extracts to scavenge the $DPPH^{cdot}$, $ABTS^{{cdot}+}$, and $OH^{cdot}$. In addition, the reducing power, phosphomolybdenum reduction, $Fe^{2+}$ chelation, antihemolytic activity, and inhibition of peroxidation were also assessed. The acetone extract of roots contained relatively higher levels of total phenolics (35.1 g/100 g extract), and possessed significant free radical scavenging and antioxidant properties. Whereas, the hot water extract of aerial parts exhibited the maximum iron chelation. The results obtained in the in vitro models clearly suggest that, M. tridentata is a natural source for antioxidants and validate the folkloric use of the plant.