Objectives This study aimed to investigate the differences in complications between hepatitis B virus (HBV)-related and alcohol-related cirrhoses. Methods Medical records of patients with HBV-related and alcohol-related cirrhoses treated from January 2014 to January 2021 were, retrospectively, reviewed. The unadjusted rate and adjusted risk of cirrhotic complications between the two groups were assessed. Results The rates of hepatocellular carcinoma (HCC) and hypersplenism were higher in HBV-related cirrhosis (both P < 0.05), whereas the rates of hepatic encephalopathy (HE) and acute-on-chronic liver failure (ACLF) were higher in alcohol-related cirrhosis (both P < 0.05). After adjusting for potential confounders, HBV-related cirrhotic patients had higher risks of HCC (odds ratio [OR] = 34.06, 95% confidence interval [CI]: 4.61–251.77, P = 0.001) and hypersplenism (OR = 2.29, 95% CI: 1.18–4.42, P = 0.014), whereas alcohol-related cirrhotic patients had higher risks of HE (OR = 0.22, 95% CI: 0.06–0.73, P = 0.013) and ACLF (OR = 0.30, 95% CI: 0.14–0.73, P = 0.020). Conclusion Cirrhotic patients with different etiologies had different types of complications: HBV-related cirrhotic patients exhibited increased risks of HCC and hypersplenism and alcohol-related cirrhotic patients more readily developing HE and ACLF.