AIM:To investigate the association between metabolic syndrome (MetS) and the development of gallstone disease (GSD). METHODS:A cross-sectional study was conducted in 7570 subjects (4978 men aged 45.0 ± 8.8 years, and 2592 women aged 45.3 ± 9.5 years) enrolled from the physical check-up center of the hospital.The subjects included 918 patients with gallstones (653 men and 265 women) and 6652 healthy controls (4325 men and 2327 women) without gallstones.Body mass index (BMI), waist circumference, blood pressure, fasting plasma glucose (FPG) and serum lipids and lipoproteins levels were measured.Colorimetric method was used to measure cholesterol, high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C).Dextrose oxidizing enzyme method was used to measure FPG.Subjects were asked to complete a questionnaire that enquired about the information on demographic data, age, gender, histories of diabetes mellitus, hypertension, and chronic liver disease and so on.Metabolic syndrome was diagnosed according to the Adult Treatment Panel Ⅲ (ATP Ⅲ) criteria.Gallstones were defined by the presence of strong intraluminal echoes that were gravity-dependent or attenuated ultrasound transmission.