Objective To investigate the relationship between the fasting blood glucose level and the severity of coronary artery disease among the Kazakh population in Xinjiang. Methods A total of 411 Kazakh patients with no known history of diabetes mellitus were enrolled in this study for highly suspected of coronary artery disease(CAD) and subesquently underwent coronary artery angiography. Coronary artery disease was diagnosed in 280 patients after coronary artery argiography. The severity of the disease was expressed in terms of Gensini score. All subjects were classified into 4 groups according to the level of fasting plasma glucose (FPG)< 5.6 mmol / L, 5.6-6.1 mmol / L, 6.1-7.0 mmol / L and ≥7.0 mmol / L. All the biochemical parameters, clinical data and coronary artery angiographic data were compared, and the possible risk factors related to the severity of coronary artery disease were studied. Results Multivariate logistic regression analysis showed that FPG was significantly associated with coronary artery disease(OR 1.53, 95% CI 1.25-1.87,P<0.001).The results showed that the prevalence of angiographic CAD and the Gensini score increased with the increasing FPG levels among the four groups.The FPG level was significantly correlated with the Gensini score (P<0.001). Conclusions FPG is significantly associated with coronary artery disease and its severity in the Kazakh population in Xinjiang.