A total of 2,584 healthy residents in the Yaeyama District of Okinawa, Japan, were investigated in 1984 to determine the prevalence of gallstone disease and its associated factors. Diagnosis of gallstone disease was assessed by real-time ultrasonography. For participants over 20 years of age, obesity index and serum levels of total cholesterol and triglycerides were measured. Overall prevalence of gallstone disease was 3.2%. Prevalence increased with age from 0% under 19 years of age to 11.4% over 70 years of age and was higher in females (4.0%) than in males (2.5%). The results of the logistic regression analysis indicated that age and fatty liver were significant predictors of gallstone disease. The results of the automatic interaction detector analysis indicated that age and fatty liver were strong factors associated with gallstone disease and that prevalence was highest in females over age 50 with fatty liver.