Serum prolactin levels were determined following stimulation by sulpiride in 20 patients with nonalcoholic liver cirrhosis and 10 normal controls. Prolactin response was essentially the same in the two groups. Only 5 cirrhotics, all with ascites, showed a lower prolactin response after sulpiride stimulation. This was interpreted as a consequence of a rapid prolactin escape from blood into the ascitic fluid, as it was shown to be the case in 2 of these patients. It is concluded that prolactin secretion in nonalcoholic liver cirrhosis is essentially normal. The higher prolactin levels found by others in alcoholic cirrhosis could be the result of a direct effect of alcohol on hypothalamic structures involved in prolactin secretion.