Bone mineral density (BMD) of the lumber vertebrae and factors related to bone metabolism were determined in patients with chronic viral hepatitis and patients with liver cirrhosis to clarify correlations between hepatic dysfunction, considered to be one of the causes of hepatic osteodystrophy, and decrease in bone mass. BMD of the second to fourth lumbar vertebrae was determined with a Lunar (Madison, WI, USA) DPX, a dual-energy X-ray absorptiometry diagnostic system. BMD was significantly lowest in patients with liver cirrhosis, followed by patients with chronic hepatitis, and healthy subjects, in this order. There was a significantly positive but weak correlation between albumin and BMD. Levels of 25(OH)D and 1,25(OH)2D were significantly lower in patients with liver cirrhosis than in those with chronic hepatitis. BMD and vitamin D were decreased in all patients whose cholinesterase (ChE) was below 0.3 delta pH. Urinary pyridinoline (Upyr) was significantly higher in the patients with liver cirrhosis, in whom bone mass was decreased, than in the patients with chronic hepatitis, whereas serum osteocalcin levels were distributed in the upper normal range in patients with chronic hepatitis and those with liver cirrhosis. There was a positive correlation between 25(OH)D and serum osteocalcin levels in patients with liver cirrhosis. These results indicate that osteogenesis is decreased and suggest that the decrease in BMD which occurs in viral liver cirrhosis, probably related to decreased, bone formation and slight promotion of bone resorption, reflects deranged hepatic function. This is the first report of Upyr and urinary deoxypyridinoline (UDpyr) determination in patients with liver cirrhosis and patients with chronic hepatitis. The negative correlation of Upyr and UDpyr with ChE is a novel finding.