In the period 1970 to 1987, 171 patients with small-intestinal mucosal atrophy have been hospitalized in our department. Of these, 132 patients fulfilled the diagnostic criteria of coeliac disease on the basis of histologic findings and clinical improvement on a gluten-free diet. Aspartate aminotransferase (ASAT), alanine aminotransferase (ALAT), and alkaline phosphatase (ALP) were chosen as markers of hepatic involvement. Elevation above the normal range in one or more of these tests was seen in 62 patients (47.0%, group I). In 70 patients (53.0%, group II) of similar age the levels of these variables were normal. In group I, 14 (10.6%) patients had an elevation of ALP only, leaving 48 (36.4%) patients with pathologic values for one or both transaminases. In group I, 32 patients had their ASAT, ALAT, and ALP reexamined after at least 6 months of gluten-free diet. Among the patients with increased values of one or both transaminases 18 patients were tested before and at least 6 months after start of gluten-free diet. The variables were significantly reduced in all patients. Liver biopsies were performed in 37 patients, and findings were normal in 5. In 25 patients the changes were classified as non-specific. Chronic active hepatitis was demonstrated in five patients. In one of these patients primary sclerosing cholangitis and ulcerative colitis were also diagnosed. Concomitant malignant disease was found in 22 patients, of whom 16 had malignant lymphoma. Malignant disease was seen more often in group I than group II (p less than 0.01). In conclusion, liver lesions were found in a great proportion of the patients with coeliac disease.(ABSTRACT TRUNCATED AT 250 WORDS)