Abstract The contamination of food and feedstuff with mycotoxins represents worldwide problem for both humans and animals. Citrinin, one of the well known mycotoxins, which was first isolated from Penicillium citrinum, is produced by more than 10 species of fungi, and is possibly spread all over the world. However, the information on the mode of toxin action is limited. Citrinin has been suggested as a causative factor in renal disease and death among livestock, poultry and perhaps humans as well since it is commonly found in food samples. Nephrotoxicity is produced in swine by feeding grain contaminated with P. citrinum. This study deals with the effect of dry lemon extract on some biochemical parameters and histological changes on kidneys of male Wister Lewis rats after being found to be moldy and having residues of citrinin mycotoxin. Fifty inbred weaned white male Wistar Lewis rats were divided randomly into 5 groups (10 rats each) control group was daily gavaged with distilled water. The four treated groups were daily gavaged with a soup lemon extract (2ml/kg B.W) for 2 weeks (T1), double the dose (T2), triple the dose (T3). Group T4 was gavaged (2ml/kg B.W) of yellow lemon soup for 2 weeks. Sera from all groups were collected to measure several biochemical indicators to assess kidney function, such as urea (BUN) and creatinine (SCr). Serum BUN increased significantly in all treated groups as compared to control. Also, serum SCr increased significantly in all treated groups as compared to the control. On the other hand, total antioxidant concentration was significantly lower in all treated groups as compared to the control. However, alpha fetoprotein and carcinoembrionic antigen remained unchanged while pyruvate kinase isoenzyme M2 was decreased significantly. Histopathological changes of rat kidney revealed tubular degenerative changes in (T3) which explain biochemical changes. In conclusion, the uses of dry lemon as a traditional food supplement in the Gulf region may pose some risk of food poisoning due to the presence of citrinin.