Chronic alcohol abuse leads to malnutrition, and thus to the deficiency of many nutrients, including vitamins and trace elements. Most often comes to the deficiency of all vitamins, however because the clinical implications, the most important is folic acid (vitamin B9) deficiency. Biochemical effect of folate deficiency is elevated homocysteine concentration in the blood, named "cholesterol of XXI. century". In the paper, the folate and homocysteine metabolism in alcohol abuse was discussed. Mechanisms of alcohol action on folate homeostasis in the human body have been indicated. Chronic alcohol consumption leads to deficiency of this vitamin due to their dietary inadequacy, intestinal malabsorption, decreased hepatic uptake and increased body excretion, mainly via urine. The decreased concentration of serum folic acid may occur in 80% of alcoholics. The cause of elevated concentrations of homocysteine in the serum of alcohol abusers is also a deficiency of vitamins involved such as vitamin B12 and pyridoxal phosphate. Disturbance of folic acid and homocysteine metabolism in alcohol abusers can lead to serious clinical consequences. Folic acid deficiency leads inter alia to macrocytic and megaloblastic anemia and neurological disorders. Megaloblastic anemia occurs in about half of alcohol abusers with chronic liver diseases. In turn, high level of homocysteine in blood is associated with an inreased risk of cardiovascular diseases. Hyperhomocysteinemia is an independent risk factor that favors the occurrence of acute coronary syndromes in patients with coronary heart disease.