In recent years， the cellular and molecular mechanisms of neuroinflammation in addictive behavior have become increasingly prominent. Alcohol abuse interacts directly or indirectly with the neuroimmune system， producing central immune signals， changing the expression and signaling of neuroimmune genes and leading to addiction. Microglia are primary modulators of the neuroimmune responses and inflammation in the central nervous system（ CNS）. This paper reviews literature relating to long-term alcohol exposure and microglia activation， highlighting that microglia are critical regulators of alcohol responses in the CNS， which will be essential for the development of better therapeutics for alcohol dependence.