Exposure to gamma radiation causes oxidative stress and generation of reactive oxygen species, which cause hepatocellular apoptosis, so it is necessary to safe the living organisms especially humans and animals. Red beetroot (Beta vulgaris L.) is thought to be crucial for enhancing hepatic health. Male Wistar albino rats were designated to evaluate the possible protective role of red beetroot peel extract (RBPE) to alleviate oxidative stress that associated with gamma-ray exposure. Biochemical, histopathology, and immunehistochemical analyses of rat livers exposed to acute radiation dose revealed different apoptotic patterns. According to the findings, RBPE has a DPPH (2,2-diphenyl-1-picryl-hydrazyl-hydrate) scavenging activity of 1.22±0.23 mg TE/g. The total phenolic and flavonoid contents of RBPE were 126.21±0.39 mg GE/g and 67.18±0.78 mg QE/g, respectively. Results showed that pre-administration of RBPE (50 mg/kg body weight for two weeks before and after exposure to 6 Gy gamma irradiation reduce elevations in liver enzymes and apoptotic markers [caspase-3, and B-cell lymphoma-2-associated protein X (Bax) and elevate the expression of the B-cell lymphoma-2 (Bcl-2). These findings were supported by the histological analyses, which demonstrated that RBPE shielded the rats' livers against gamma-irradiation-induced damage. The protective effects are most likely due to the potent antioxidant phenols in RBPE that working together synergistically. It is concluded that RBPE is a promising radioprotector for liver against oxidative stress induced by exposure to gamma ionizing radiation due to its antioxidant and anti-apoptotic power.