SummaryDuring 1972 and 1973, 33 alcoholic in‐patients, probably representative of alcoholism of more than 3 years duration in a predominantly urban population of 310,000, were investigated. Data relating to serum folate and B12 values, and haemoglobin, red and white blood count, mean corpuscular haemoglobin and mean corpuscular haemoglobin concentration, were obtained and compared with similar findings from 239 patients with other psychiatric conditions admitted over the same period. The groups did not differ significantly with respect to mean folate or B12, but there were significantly more folate values greater than 4.9 ng/ml among the alcoholics than among the other patients. Twenty four percent of alcoholics and other patients were malnourished. The mean folate of the malnourished alcoholics was significantly lower than that of the adequately nourished alcoholics. Significantly more alcoholics than other patients showed low RBC, macrocytosis and high MCH. Macrocytosis among the alcoholics was not satisfactorily accounted for by low folate and B12, or hepatic dysfunction. Sixty seven percent of the alcoholics were macrocytic, and seventy five percent had macrocytosis and/or elevated MCH. It was felt that the data were consistent with impaired haemapoiesis in alcoholism and that MCV and MCH were useful pointers to the diagnosi