Aims: Previous studies reported that serum myostatin is associated with sarcopenia. We aimed to elucidate the association between serum myostatin levels and hepatocellular carcinoma (HCC) development in patients with alcoholic liver cirrhosis (ALC). Methods: This retrospective multi-center study assessed 201 ALC patients from 2010 to 2016 in four university-affiliated hospitals in Korea. The primary endpoint was development of HCC within 5 years. Index date was time when patients were admitted into hospitals for control of complications from liver cirrhosis. The Cox proportional hazards model analysis was used to assess the association of serum myostatin levels and HCC development in ALC patients. Area under receiver operating characteristic curve (AUROC) of serum myostatin levels for 5-year HCC development was calculated. Serum myostatin levels were measured by enzyme-linked immunosorbent assay using samples which were collected at the index date. Results: During a median follow-up of 2.1 years, 5-year cumulative HCC incidence rates were 8.0% in total population (n=201). The median levels of serum myostatin was 3.6 ng/mL (interquartile [IQR], 2.2-6.6 ng/mL). The AUROC of serum myostatin levels for 5-year HCC development was 0.78 (95% CI, 0.70-0.82). When total patients were divided according to serum myostatin levels, there was a significant difference of HCC development within 5 years between low myostatin group and high myostatin group (HR 4.52, P=0.04). 5-year cumulative HCC incidence rates were 3% in the low myostatin group (n=100); 5-year cumulative HCC incidence rates were 12% in the high myostatin group (n=101). In Cox proportional hazards model analysis, age and serum myostatin levels were an independent risk factor for HCC development (adjusted HR [aHR] of age 1.06, P=0.004 and aHR of myostatin 1.15, P=0.02). Conclusions: Higher serum myostatin levels were significantly associated with a higher risk of HCC development in ALC patients. Serum myostatin levels showed good predictive performance of 5-year HCC development in ALC patients. Serum myostatin levels may represent a promising predictive biomarker in ALC patients, which could identify high-risk patients who need a stringent surveillance.