Abstract : The present study aimed to evaluate the metabolic, biochemical and genetic alteration associated with the consumption of classical (CKD) and modified ketogenic (MKD) diet in metabolic syndrome rats. Sixty healthy adult male albino rats divided into six groups 10 rats each as follow: Group (1): Healthy rats fed on a standard balanced diet for 6 weeks. Group (2): Healthy rats fed on a classic ketogenic diet for 6 weeks. Group (3): Healthy rats fed on Modified ketogenic diet for 6 weeks. Group (4): Metabolic syndrome induced rats fed on a standard balanced diet for 6 weeks. Group (5): Metabolic syndrome induced rats fed on a classic ketogenic diet for 6 weeks. Group (6): Metabolic syndrome induced rats fed on Modified ketogenic diet for 6 weeks. Metabolic syndrome induced rats consumed classical or modified Atkins diet showed amelioration in the levels of blood glucose, insulin and hemoglobin A1C. Also, the two types of ketogenic diet reduced the levels of MDA and oxidized-LDL in the metabolic syndrome rats with an increase in SOD activity. Classical ketogenic diet or modified ketogenic diet caused a significant (p≤0.05) decrease in β-hydroxybutyrate dehydrogenase (BHPD) and uncoupling protein (UCP-1) with a decrease in peroxisome proliferator-activated receptor (PPAR-α) genes expression compared to metabolic syndrome group. Also, there was a significant (p≤0.05) elevation in acetoacetate (AA), B-hydroxy butyrate, (BHB) and HMG-COA-Synthase 2 with a decrease in Carnitine Palmitoyl Transferase (CPT) compared to metabolic syndrome group. Based on our results ketogenic diet has promising effect in ameliorating metabolic and biochemical alterations associated metabolic syndrome.