Objective:To explore the relationship between atherosclerotic index of plasma(AIP)and vulnerable plaque of coronary under computed tomography(CT)based on coronary CT angiography(CCTA).Methods:Data were retrospectively collected on 213 patients with coronary heart disease(CHD)who underwent CCTA examination from January 2021 to February 2024 at the Second Affiliated Hospital of Shenyang Medical College,and they were divided into a vulnerable plaque group(123 cases)and a non-vulnerable plaque group(90 cases)according to whether existed vulnerable plaque of coronary artery.General clinical data such as age,gender,history of smoking,history of alcohol consumption,history of diabetes,and serum indicators such as AIP were collected.The differences in AIP and other factors between the two groups were compared.The independent influencing factors of vulnerable plaque of coronary artery were determined by multifactorial logistic regression analysis,and the predictive value of AIP for vulnerable plaque was assessed by drawing a receiver operating characteristic(ROC)curve.Results:AIP of vulnerable plaque group was 0.22±0.31,which was higher than that 0.05±0.27 of the vulnerable plaque group,and the difference of AIP between two groups was significant(t=4.223,P<0.001).Multifactorial logistic analysis showed there was independent correlation between AIP and vulnerable plaque under CT(OR=7.556,95%CI:2.442～23.385,P=0.002).The ROC curve showed that the best cut-off value of AIP was 0.20 in predicting vulnerable plaque under CT,and the value of area under curve(AUC)was 0.665,and the sensitivity was 55.56%and the specificity was 73.98%.Conclusion:AIP is an independent influencing factor for CHD patients who complicate vulnerable plaques,and it has a certain of predictive value for vulnerable plaques.