Abstract: Recent studies have demonstrated a clinical relation between steatohepatitis and atherosclerosis. Both pathologies are of much interest due to the great morbidity and mortality associated with them and studies in animal models are necessary in order to find new therapies. The aim of the present study was to establish a new model for the simultaneous study of preclinical atherosclerosis and non-alcoholic steatohepatitis, in which BALB/c mice were fed a high-fat canine puppy diet. An experimental study was carried out on 3 BALB/c mice groups that were fed a standard diet (SDiet), a commercial atherogenic diet (AtheroDiet), or a canine puppy diet (CanDiet), for 6 months. A biochemical serum test and an intraperitoneal glucose tolerance test were carried out. The animals were euthanized at the sixth month and histopathologic slices of the liver and the thoracic and abdominal aorta were stained with hematoxylin and eosin or Masson's Trichrome. Steatohepatitis was evaluated and the thoracic and abdominal aortic intima-media thickness was measured. The ANOVA test was used for the group comparison. Steatosis and inflammation of the liver and thoracic and abdominal aortic intima-media thickness were all significantly increased in the AtheroDiet and CanDiet groups, compared with the SDiet group (p = 0.000). There was a positive correlation between steatohepatitis and the aortic intima-media thickness. No significant differences were found among the groups in relation to serum cholesterol or triglyceride levels; however, there was an alteration in the glucose tolerance curve in the AtheroDiet and CanDiet groups with respect to the SDiet group. There was no evidence of hepatic fibrosis in any of the groups. In conclusion, we were able to create a low-cost and accessible murine model for the simultaneous study of steatohepatitis and preclinical atherosclerosis.