Objective To explore the relationship between metabolic syndrome and nonalcoholic fatty liver disease in adults. Methods A total of 144 subjects diagnosed as fatty liver by type B ultrasonography without history of alcohol were enrolled as NAFLD group from 1 034 workers in a power plant in Shanxi in 2007.And 147 subjects without fatty liver by type B ultrasonography were selected as control group.The levels of ALT,TC,TG,FBG,SBP,DBP and BMI were measured,and compared between two groups. Results In NAFLD group,the levels of ALT,TC,TG,FBG,SBP,DBP and BMI were significantly higher than those in control group.The prevalence of obesity(77.78%),hypertension(23.61%),hyperglycemia(25.69%),dyslipidemia(67.36%)and metabolic syndrome(39.58%)in NAFLD group were significantly higher than those in control group. Conclusion Nonalcoholic fatty liver disease is closely related with metabolic syndrome.