The mortality experience of 1392 lead-zinc-silver miners (Gorno, Northern Italy) employed in the period 1/1/1950-31/12/1980 and followed-up to 31/12/1986 was examined. Two separate estimates of the radon exposure level are available: 0.60 and 0.36 working levels respectively. The silica exposure level was not assessed. Vital status was ascertained for 95.6% of the cohort members and their mortality was compared with expected deaths based on national rates. Significant excess mortality from esophageal cancer, stomach cancer, lung cancer, respiratory tuberculosis, respiratory diseases and deaths from external causes was found among underground miners. Surface workers show significantly increased mortality from liver and bile ducts cancer, hepatic cirrhosis, respiratory tuberculosis and respiratory diseases. Based on the 16.4 excess lung cancer cases among underground miners and their cumulative radon exposure, an attributable risk estimate ranging from 9.78 and 16.31 cases per million person-years and WLM (Working Level Month) was calculated.