Gallstone disease is a major surgical problem in many populations; it is probably related to diet, especiallyexcessive consumption of meat. The objective of this study was to determine the chemical composition ofgallstones and their association with neoplastic changes including cholangiocarcinomas in cholecystectomisedpatients. The chemical composition of gallstones from 40 patients (8 males and 32 females) was analyzed. Thisis a prospective study performed in Baquba teaching hospital in the period from 1/10/2012 to 1/1/2013 in whichwe collected the gallstones for the patients who underwent cholecystectomy, whether open or laparoscopic. Thestones were classified according to their chemical composition as a mixed stones (MS), and examined using astone analysis set (chemical qualitative method) for calcium, magnesium, phosphate, uric acid and oxalate whichwas used reagent for qualitative determination of main individual components of stones. The results of this studyshowed the highest incidence of gallstones in the age group 40-49 was 13 cases followed by 11, 8 and 4 cases forage groups 30-39, 50-59, 20-29 and 60 and above, respectively. The chemical analysis showed the majority ofgallstones were mixed, 38 containing calcium followed by 37 cases with uric acid, 28 with magnesium, and 25 and22 stones with oxalate and phosphate, respectively. Microscopically, we confirmed neoplastic changes (17.5%)as cholangiocarcinomas (CCCs) (7.55%) and dysplastic cells of carcinoma in situ in 4 (10%), 31 (77.5%) caseswere chronic cholecystitis and 2 (5%) cases were acute cholecystitis with empyema out of bile duct disorderspatients. In conclusion, majority of cases had mixed gallstones that involved five and four of inorganic chemicalsof calcium, magnesium and phosphate, the highest incidence of gallstones in age group 40-49 years old was 13cases, and neoplastic changes were confirmed (17.5%) including CCCs, (7.5%) and dysplastic cells of carcinomain situ (10%), while 31 (77.5%) cases were chronic cholecystitis.