The study focused on investigation of antioxidant potential of different extracts of immature and mature garlic bulbs. Antioxidant activity was assessed by measuring the reducing power, scavenging activity of extracts of Allium sativum on 2,2-diphenyl-1-picrylhydrazyl (DPPH). Total phenolic and flavonoid contents were also checked. The results showed that garlic had significant antioxidant potential. Vegetative garlic had more antioxidant potential compared to old mature garlic except in TPC. Sulphur compounds, flavonoids and phenolic compounds are responsible for antioxidant activity of garlic. Due to high antioxidant potential, garlic can protect DNA from destruction to some extent.