Background and objective. Steatohepatitis is a common cause of liver disease due to alcohol (ALD) or non-alcoholic fatty liver disease (NAFLD). We performed this study to compare natural history of ALD and NAFLD. Material and methods. Retrospective analysis of ALD or NAFLD patients managed at our center (2007-2011). ALD diagnosed by excluding other liver diseases (except HCV) and alcohol abuse of > 40 g/d in women and > 60 g/d in men for > 5 years. NAFLD diagnosed by excluding other liver diseases and a history of alcohol use of < 10 g/d. Cirrhosis was diagnosed using biopsy for uncertain clinical diagnosis. Results. Compared to patients with NAFLD (n = 365; mean age 50 yrs; 43% males; 53% diabetic), ALD patients (n = 206; mean age 51 yrs; 68% males; 24% diabetic) presented more often with cirrhosis or complications(46vs. 12%; P< 0.0001) with a higher MELD score (13 ±7 vs. 8 ± 8; P<0.0001). On logistic regression, ALD diagnosis was associated with presence of cirrhosis by over 4-fold (4.1 [1.8-9.1]) even after excluding 23 patients with concomitant HCV. Over median follow up of about 3 and 4 yrs among ALD and NAFLD patients respectively, ALD patients more frequently developed cirrhosis or its complications including HCC with worse transplant free survival (90 vs. 95%; P = 0.038). Conclusions. Compared to NAFLD, ALD patients present at an advanced stage of liver disease with a faster progression on follow-up. Prospective multicenter studies are needed to identify potential barriers to early referral of ALD patients as basis for development of strategies to improve outcome of patients with ALD.