BACKGROUND:The prevalence of gallstones is low in Asians.In Iran,many factors influence the prevalence of this disease.The aim of this study was to determine the prevalence of gallbladder stones and their chemical characteristics in a population by the study of cadavers. METHODS:In this cross-sectional study,autopsies were performed on 253 cadavers of more than 13 years old.The cadavers were studied to determine the number,location of stone formation,chemical composition,dry weight,and mean diameter of stones in the gallbladder and common bile duct. RESULTS:The prevalence of gallstone disease in these cadavers was 6.3%(men 4.7%,women 8.6%,not significantly different,P=0.216).There was a positive relationship between the age and prevalence of gallstone disease(P=0.033).The most common stone compositions were cholesterol and oxalate.The mean diameter (P=0.0058)and dry weight(P<0.0001)of stones were higher in the gallbladder than in the common bile duct. Positive relations between the amount of oxalate and mean diameter,and between the amount of oxalate and mean dry weight of gallstones were found,but the relationship between the amount of cholesterol and mean diameter was inverse. CONCLUSIONS:The prevalence of gallstones differed among age groups.Diameter and dry weight of gallstones were dependent on location of stone formation and chemical composition. BACKGROUND: The prevalence of gallstones is low in Asians.In Iran, many factors influence the prevalence of this disease. The Aim of this study was to determine the prevalence of gallbladder stones and their chemical characteristics in a population by the study of cadavers. METHODS : In this cross-sectional study, autopsies were performed on 253 cadavers of more than 13 years old.The cadavers were studied to determine the number, location of stone formation, chemical composition, dry weight, and mean diameter of stones in the gallbladder and common bile duct. RESULTS: The prevalence of gallstone disease in these cadavers was 6.3% (men 4.7%, women 8.6%, not significant different, P = 0.216). There was a positive relationship between the age and prevalence of gallstone disease (P = 0.033). Most common stone compositions were cholesterol and oxalate. The mean diameter (P = 0.0058) and dry weight (P <0.0001) of stones were higher in the gallbladder than in the common bile duct. Positive relations between the amo unt of oxalate and mean diameter, and between the amount of oxalate and mean dry weight of gallstones were found, but the relationship between the amount of cholesterol and mean diameter was inverse. CONCLUSIONS: The prevalence of gallstones differed among age groups. Diameter and dry weight of gallstones were dependent on location of stone formation and chemical composition.