This study aimed to see how induced obesity, orlistat, and aqueous rosemary extract, affected albino rats' brains and livers. The rats were divided into 7 different groups. Each group contains 6 rats. The first group was the control. The second group was fed on a high-fat diet, and the third and fourth groups were on a high-fat diet with orlistat 100 and 200 mg/kg of B.W. The fifth group on a high-fat diet with an aqueous extract of rosemary was given 10 ml/kg of B.W. The sixth and seventh groups were given an aqueous extract of 10 ml/kg of rosemary with orlistat 100 and 200 mg/kg, respectively. The histopathological results of the brain and liver revealed pathological changes in the fattened rats, third and fourth groups represented by vacuolation of surrounding neurons and glial cells. Congestion of blood vessels and vasogenic edema in the brain while in the liver were fatty degeneration in the hepatocytes, necrosis and lymphocytic aggregation, congestion and dilatation of blood vessels, hyperplasia of epithelial cells lining bile ducts, focal infiltration of inflammatory cells and dilatation of sinusoids compared with the control group and fifth group. Whereas the histopathological changes of the sixth and seventh groups were less severe than the lesion that occurred in the second, third and fourth groups. We conclude that the aqueous extract of rosemary was efficient in alleviating tissue pathological lesions.