Sorafenib is the new reference standard for patients with advanced hepatocellular carcinoma (HCC). To identify prognostic factors in sorafenib-treated HCC patients and to evaluate outcomes with respect to liver function. In this retrospective study, 148 HCC patients received sorafenib 400 mg b.d. across 11 Austrian institutions. Seventy-eight HCC patients who received best supportive care (BSC) in the pre-sorafenib era served as a control. In sorafenib-treated patients, low baseline α-fetoprotein, low Child-Pugh (CP) score, compensated cirrhosis, and low baseline aspartate aminotransferase (AST) were associated with significantly longer overall survival (OS) on univariate analysis. CP score and baseline AST remained independent prognostic factors on multivariate analysis. In patients with Barcelona Clinic liver Cancer (BCLC) stage B or C HCC (sorafenib: n = 139; BSC: n = 39), CP-A patients had a median OS of 11.3 (sorafenib [n = 76]) vs. 6.4 (BSC [n = 17]) months (P = 0.010), and CP-B patients had a median OS of 5.5 (sorafenib [n = 55]) vs. 1.9 (BSC [n = 22]) months (P = 0.021). In the sorafenib group, median OS according to baseline AST was 11.8 (<100 U/L [n = 58]) vs. 3.9 (≥100 U/L [n = 15]) months for CP-A patients (P = 0.127), and 6.5 (<100 U/L [n = 33]) vs. 2.1 (≥100 U/L [n = 21]) months for CP-B patients (P = 0.011). There was no survival difference between sorafenib and BSC in patients with BCLC stage D HCC (1.5 vs. 1.4 months; P = 0.116). Sorafenib was associated with improved survival in both CP-A and CP-B patients. In CP-B patients, baseline AST may be helpful in determining which patients are most likely to benefit from sorafenib.