Acute and chronic alcohol abuse are common conditions in patients admitted to hospitals. Alcohol has widespread direct and indirect effects on the hematologic system which can mimic and/or obscure other disorders. Leukocyte, erythrocyte, and thrombocyte production and functions are affected directly. Liver damage secondary to alcohol abuse also impacts red blood cells also impacts red blood cells and the hemostatic mechanisms. Nutritional deficiencies are caused not only by poor dietary habits practiced by alcohol abusers, but by the effect of alcohol on the absorption, storage, and utilization of several vitamins. Identifying these numerous effects results in a more comprehensive and clinically accurate understanding of the patients hematologic status.