Objective To investigate the application value of the plasma homocysteine (Hcy) ,folic acid (FA) and vitamin B12 (VB12 ) levels in the patients with coronary heart disease (CHD) and CHD complicating impaired glucose tolerance (IGT) .Methods 80 triers screened by the inclusion criteria were divided into the simple CHD group (36 cases) and the CHD complicating IGT group(44 cases);70 healthy cases were taken as the controls .Hcy ,FA and VB12 levels were measured and the detection results were performed the statistical analysis .Results The Hcy level in both experimental groups were higher than that in the control group , the difference was statistically significant (P<0 .05) ,the positive rates were 94 .4% in the simple CHD group and 88 .6% in the CHD complicating IGT group respectively ;The plasma FA level in both experimental groups were lower than that in the control group ,meanwhile ,plasma Hcy level and FA level showed a negative correlation (P<0 .05);The VB12 level had no statistical differ-ence among 3 groups (P>0 .05) ,and the correlation analysis between the Hcy level in the two experimental groups with VB 12 had no statistical significance (P>0 .05) .Conclusion Plasma Hcy level in CHD and CHD complicating IGT is very high and negatively correlated with the FA level ,dynamically detecting the Hcy level has an important significance for early warning and treatment of CHD and CHD complicating IGT .