The food-borne 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) is a potential human carcinogen abundant in cooked meat. While circadian rhythms are crucial biological oscillations, the negative impact of PhIP on circadian systems and the potential of mitigation remain underexplored. We investigated the effects of PhIP on circadian rhythms and the mitigating effects of the phytochemical antioxidant pterostilbene (PSB) in Caenorhabditis elegans. We show that exposure to 10μM PhIP disrupts the 24-h circadian rhythms of C. elegans, an effect mitigated by co-exposure to 100μM PSB. In addition, PhIP-induced circadian disruption can be linked to defective oxidative stress resistance, which is associated with the DAF-16/FOXO pathway and is modulated by PSB. Molecular docking suggested that PhIP and PSB bind similarly to DAF-16. Moreover, 10μM PhIP abolished the rhythmic expression of the core clock gene prdx-2, which is restored by 100μM PSB. Findings from this study provide novel insight of how food-borne contaminant like PhIP may contribute to the disruption of circadian rhythms and suggest potential for PSB to mitigate these effects in higher organisms.