Alcoholic liver disease (
ALD
) is a progressive liver disease that can cause a series of complications, including cirrhosis, liver failure and hepatocellular carcinoma. Granulocytic myeloid‐derived suppressor cell (
gMDSC
) populations have been observed to expand in various liver diseases and to inhibit innate and adaptive immunity in patients with liver disease. However, the characteristics of
gMDSC
s in patients with
ALD
have not been studied. We studied 24 healthy controls (
HC
s) and 107 patients with
ALD
and found an accumulation of
gMDSC
s in the peripheral blood of patients with alcoholic liver cirrhosis (
ALC
). Furthermore,
ALC
patients with a poor prognosis displayed a significant increase in peripheral
gMDSC
s and showed an increased capacity for arginase I production compared to
HC
s. In contrast, plasma arginase I levels in
ALC
patients were negatively correlated with total bilirubin and international normalized ratio, two key parameters of liver damage. Importantly,
gMDSC
s accumulated in the livers of
ALC
patients, and the frequency of liver
gMDSC
s significantly correlated with that of peripheral
gMDSC
s. In addition,
gMDSC
enrichment in vitro significantly inhibited the function of natural killer (
NK
) cells, perhaps preventing the
NK
‐induced apoptosis of hepatic stellate cells. In summary, increased peripheral and intrahepatic
gMDSC
populations are present in patients with
ALC
and may contribute to enhancing the severity of liver cirrhosis.