A number of hematological variables have been investigated and followed during a hospital stay in a group of 34 non‐cirrhotic male alcoholics after acute drinking bouts. The most prominent findings were a rise in reticulocytes, a fall in serum iron and a rise in WBC, especially with respect to the lymphocytes. HB and hematocrit values both fell during hospitalization, while ESR and serum haptoglobin rose. No change was observed in the platelet count. It is concluded that alcohol has marked effects on the hematological system even in subjects without serious liver damage. The results underline the importance of an adequate knowledge of the patient̂s alcohol habits in the investigation of obscure hematologic abnormalities.