Backrround Syntax score (SS),an angiographic tool to grade the complexity of coronary artery disease,has prognostic importance for this disease.C-reactive protein (CRP) and albumin are indicators of inflammation.And both of them are associated with high SS.Hence,we aimed to investigate whether baseline CRP to albumin ratio (CAR) is associated with SS.Method A total of 312 consecutive patients with stable angina pectoris,who underwent coronary angiography for suspected coronary artery disease (CAD) from January 2018 to May 2019,were classified into two groups,low score group (syntax score≤22) and high score group (syntax group＞22).The Multivariate logistic analysis and ROC curve were performed to detect the predictive effect of CAR for higher SS.Results There are 163 cases in the low score group while 149 cases in the high score group.CAR in the high score group was significantly higher than the other group(5.6[2.8-9.6]vs.2.5[1.7-5.2],P＜0.01).In multivariate logistic regression analysis,CAR was proved to be an independent predictor for high syntax score.ROC curve analyses reveal the good predictive values of CAR (AUC 0.731,95％ CI: 0.608-0.814,P＜0.01) for high syntax score and statistical significant better than CRP or albumin alone.Conclusions CAR is independently associated with the complexity and severity of CAD,which has better predictive value than CRP or albumin alone.