Abstract: Abstract Objective: To study the risk factors of metabolic syndrome by the cases of Tianjin policemen within different ages. Methods: 1250 policemen were divided into MS group and non- MS group by their clinical dates, and the changes of the levels of liver function, renal, lipid, heart rate, WBC, PLT, FIB and ESR which were analyzed. The policemen have been divided into two groups as less than 40 years old and over 40 years old group to study the difference of the risk factors of MS by the two groups. Result: MS group on alanine aminotransferase(ALT), alkaline phosphatase(ALP), γ-glutamyl transferase(gamma GT), total protein(TP), albumin(ALB), globulin(GLB)，uric acid (UA), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), heart rate (HR), WBC and FIB were significantly higher than non-MS group, however, the high-density lipoprotein cholesterol (HDL-C) levels were significantly lower than non-MS group, the difference was statistically significant (P<0.05). The risk factors of the policemen under the age of 40 are serum alanine aminotransferase, UA, FIB, and HR. while the risk factors beyond the age of 40 are serum total protein, UA, gamma GT, WBC, and HR. Conclusion: FIB is high-risk factors for MS under the age of 40.