Objective Evaluation of left ventricularthe myocardium systolic function in patients with coronary atherosclerotic heart disease (coronary heart disease) by two-dimensional speckle tracking imaging (2D-STI) and to evaluate the clinical value of 2D-STI technique in early diagnosis of coronary heart disease.Methods Selection of 138 patients with suspected coronary heart disease,according to the results of coronary angiography, patients were divided into control group (68 cases,without coronary artery stenosis), group A( 28 cases ,coronary artery stenosis rate < 50%), group B(22 cases Coronary artery stenosis rate 50% to 75%) and group C (20 cases, coronary artery stenosis rate ≥ 75%).Measurement of longitudinal, circumferential and radial systolic peak strain of ischemic myocardial segments in left ventricular basal segment, middle segment and apical segment by 2D-STI (BAS-ls,MID-ls,APE-ls,BAS-cs,MID-cs,APE-cs,BAS-rs,MID-rs,APE-rs), and compare the differences of the above parameters among the three groups.Using the results of coronary angiography as the gold standard, the sensitivity and specificity of predicting coronary stenosis rate ≥ 75% the receiver operating characteristic curve were drawn(ROC).Results The APE-ls in group B was lower than that in control group, and the BAS-ls,MID-ls,APE-ls,MID-cs,APE-cs in group C was lower than that in control group (all P＜0 05).The difference between the parameters of the remaining groups and the control group was not statistically significant.The results of ROC curve show that the peak systolic longitudinal strain peak of each ischemic myocardium is the most valuable diagnostic for severe stenosis coronary heart disease, the area of the curve is 0.853, the sensitivity is 83.3%, the specificity is 71.4%, and the cutoff value is -17.5%. Conclusion In patients with coronary heart disease without obvious left ventricular segmental wall motion abnormality, the systolic function of ischemic myocardial segments has been reduced to varying degrees. 2D-STI technique can be used to quantitatively evaluate left ventricular systolic function in patients with coronary heart disease, and further estimate the degree of coronary artery stenosis, which may become a new method for early screening of coronary heart disease.