We have compared hepatic alcohol dehydrogenase activities in chick, rat and human liver with the major alcohols in commercial alcoholic beverages. 1. 1. Chick and rat hepatic alcohol dehydrogenase was greater when assayed at a physiological pH in buffer containing chloride ions, as compared with the activity in pyrophosphate buffer at alkaline pH. 2. 2. In contrast to reports of instability of ADH to freezing, we found the enzyme from all three species stable to freezing in 0.25 M sucrose. 3. 3. Rat liver enzymatic activity was unstable in the presence of substrate, where as that of chick and human was not. 4. 4. For all three species, the K m of hepatic ADH for substrate decreased with increasing chain length of alcohols. In both chick and human samples, the V max values for the higher chain alcohols were similar to that with ethanol, while in rat samples, ADH activity was dramatically lower with the higher chain alcohols compared to ethanol.