Purpose: This in-vitro study aimed to assess the impact of natural antioxidants on free radical's removal at different time intervals. Materials and methods: A total of sixty intact upper central incisors were randomly split into four groups (n=15 each) according to the antioxidant used and all groups were bleached using gel containing 40% hydrogen peroxide (HP): G1 (control group): Bleaching with no antioxidant. G2: Bleaching followed by 5% grape seed extract solution for 10 mins G3: Bleaching followed by 5% green tea extract solution for 10 mins G4: Bleaching followed by 10% sodium ascorbate solution for 10 mins. The assessment of free radicals for each group was evaluated by colorimetric method at three-time intervals; baseline, after 24 and after 48 hrs. Results: Regarding effect of antioxidants on free radical clearance at different time intervals, results of this study showed that there was statistical substantial disparity between all groups at all time intervals. The greatest mean percentage change was recorded for sodium ascorbate, followed by green tea, then grape seed extract whereas the least value was recorded for the control. Conclusion: All the antioxidants employed in this study were capable of removal of free radicals after bleaching. It was concluded that, sodium ascorbate showed statistically significant decrease in free radicals after tooth bleaching when compared to natural antioxidants.