Background: Our planet's temperature is rising at an alarming rate, threatening the well-being of all life on Earth. This warming disrupts the growth, health, and overall productivity of humans, animals, and ecosystems. Objectives: The current study aimed to evaluate the histological alterations triggered in the liver and kidney tissues of adult mice exposed to heat stress. Methods: 15 mice were randomly divided into control group (5 mice) which were housed under standard laboratory conditions with a constant temperature of 25°C and experimental group which were divided into two subgroups, heat stress group (5 mice) where mice were exposed to a high temperature of 38°C and severe heat stress group (5 mice) where mice were subjected to an even higher temperature of 48°C, Results: Myriad histopathological changes were revealed in the liver and kidney tissues of heat stressed animals including destruction of the hepatic and renal normal structure represented by damaged cells possessing vacuoles in their cytoplasm and altered shaped nuclei which displayed signs of death, either pyknosis, karyorrhexis or karyolysis. Besides, dilatation and congestion of blood vessels. Conclusion: The current study confirms that even moderate or severe heat stress can damage the liver and kidneys, potentially leading to death. This aligns with what we know about the dangers of heatstroke. Rising global temperatures pose a significant threat to the well- being of all life on Earth. Heat stress can harm not only humans but abo animals and ecosystems