In an attempt to find a more useful clinical test for the diagnosis of liver disease, serum levels of the enzyme sorbitol dehydrogenase (SDH) were measured in patients with liver disease and patients with nonhepatic diseases. The majority of patients in both groups had concomitantly elevated serum levels of SGOT and SGPT. In the patients tested, SDH elevations were found to be specific for liver involvement, but much less sensitive than the transaminases. The serum sorbitol dehydrogenase test, in its present form, does not appear to offer any special advantages over the transaminase studies presently employed to detect hepatocellular disease. Certain conclusions can be drawn from the data: (1) SDH was found to be organ-specific but not disease-specific in the patients tested; (2) it was seen to be less sensitive than the transaminases; and (3) SDH levels remained elevated for much shorter periods of time than the transaminases.