Progressive fibrosis, liver failure and cancer are central liver-related outcomes of nonalcoholic steatohepatitis (NASH), but notoriously difficult to achieve in mouse models. We performed a direct, quantitative comparison of hepatic fibrosis progression in well-defined methionine- and choline-deficient (MCD) and choline-deficient, amino-acid defined (CDAA) diets with increasing fat content (10-60% by calories) in C57Bl/6J and BALB/cAnNCrl mice.In C57Bl/6J mice, MCD feeding resulted in moderate fibrosis at week 8 (2-fold increase in hepatic collagen content) and progressive weight loss, irrespective of fat content. In contrast, CDAA-fed mice did not lose weight and developed progressive fibrosis starting from week 4. High dietary fat in the CDAA diet model dose-dependently induced the lipid metabolism genes SREBP and SCD2, and increased the ductular reaction and fibrosis. Longitudinal analysis of CDAA with 60% fat (HF-CDAA) feeding revealed pronounced ductular reaction and perisinusoidal bridging fibrosis, with a 7-fold increase of hepatic collagen at week 12, that showed limited spontaneous reversibility. At 24 weeks, HF-CDAA mice developed signs of cirrhosis with 10-fold HYP increase, regenerative nodules, portal hypertension and elevated serum bilirubin and ammonia; 80% of mice (8/10) developed multiple hepatocellular carcinomas (HCC). High fat supplementation of MCD in C57Bl/6J, or feeding HF-CDAA diet to fibrosis-prone BALB/cAnNCrl strain failed to result in increased fibrosis.In conclusion, HF-CDAA feeding in C57Bl/6J mice was identified as an optimal model of steatohepatitis with robust fibrosis and ductular proliferations that progress to cirrhosis and HCC within 24 weeks. This model will aid the testing of interventions and drugs for severe NASH.