Objective Investigating the value of combined serum annexin A1 （AnxA1）， a disintegrin-like and metalloproteinase with thrombospondin type-1 domain 13 （ADAMTS13）， and electrocardiogram parameters in assessing the degree of coronary stenosis and plaque stability in patients with acute myocardial infarction （AMI）. Methods A total of 280 suspected AMI patients admitted to our hospital from August 2020 to August 2022 due to chest pain were collected as the study subjects， according to the results of coronary angiography and cTnl level， they were grouped into a non AMI group （135 cases） and an AMI group （145 cases）， the serum levels of AnxA1 and ADAMTS13 were compared between the two groups. According to the coronary Gensini score of AMI patients， they were grouped into the mild group （55 cases）， the moderate group （53 cases）， and the severe group （37 cases）. The serum levels of AnxA1 and ADAMTS13 were compared among patients with different numbers of coronary artery lesions and different degrees of coronary artery lesions. The receiver operating characteristic curve （ROC） was used to analyze the predictive value of serum AnxA1 and ADAMTS13 combined with electrocardiogram for severe coronary artery disease and plaque stability in patients with acute myocardial infarction （AMI）. Results Compared with the non AMI group， the serum AnxA1， QTc， and TP Tec levels in the AMI group were increased［（0.97 ± 0.26 ）vs （1.31 ± 0.38） μg/mL］ ［（417.56 ± 29.11 ） vs （456.88 ± 28.62） ms］ ［（106.53 ± 15.28） vs （120.48 ± 14.91） ms］， ADAMTS13 levels decreased ［（1.22 ± 0.39） vs（0.86 ± 0.29 ）ng/L］ （P < 0.05）. Compared with the single vessel group， the serum AnxA1， QTc， and TP Tec levels in the double vessel and multi vessel groups increased［（1.08 ± 0.15）vs（1.36 ± 0.21）vs（1.60 ± 0.25 μg/mL］ ［（439.84 ± 19.73）vs（459.73 ± 19.80）vs（479.74 ± 20.11）ms］ ［（114.82 ± 11.40）vs（121.89 ± 10.96）vs（127.41 ± 10.57） ms］， ADAMTS13 levels decreased［（1.05 ± 0.27）vs（0.82 ± 0.19）vs（0.61 ± 0.13）ng/L］ （P < 0.05）.Compared with the mild group， the serum AnxA1， QTc， and TP Tec levels in the moderate and severe groups increased ［（1.11 ± 0.14）vs（1.35 ± 0.20）vs（1.55 ± 0.27）μg/mL］ ［（438.96 ± 20.37）vs（459.44 ± 21.19）vs（479.84 ± 22.42）ms］ ［（113.43 ± 11.58）vs（121.88 ±11.39）vs（128.96 ± 11.16）ms］， ADAMTS13 levels decreased ［（1.03 ± 0.23）vs（0.88 ± 0.17）vs（0.58 ± 0.12）ng/L］ （P < 0.05）. Compared with the stable plaque group， the serum AnxA1， QTc， and TP Tec levels in the unstable plaque group were significantly increased［（1.15 ± 0.24）vs（1.46 ± 0.31）μg/mL）］ ［（440.37 ± 29.11）vs（472.29 ± 28.62） ms］ ［（112.44 ± 15.63）vs（127.98 ± 15.17）ms］， ADAMTS13 levels significantly decreased［（0.97 ± 0.18）vs（0.76 ± 0.09）ng/L］， with statistically significant difference （P < 0.05）. The ROC curve results showed that the AUC of combining electrocardiogram parameters to predict the degree of coronary artery disease in AMI was 0.948， which was better than individual detection （P < 0.05）. The ROC curve results showed that the combined prediction of electrocardiogram parameters for severe coronary artery disease in AMI had an AUC of 0.925， which was superior to their individual detection （P < 0.05）. Conclusion The combination of electrocardiogram and serum AnxA1， ADAMTS13 showed better predictive value for severe coronary artery disease and plaque stability in AMI， providing a reference for clinical diagnosis of AMI.