Objective:To explore the application value of?non-invasive left ventricular pressure-strain loop (LV-PSL) in quantitative assessment of myocardial work before and after percutaneous coronary intervention (PCI) in patients with coronary artery disease（CAD）. Methods: thirty CAD patients who were scheduled to undergo PCI in the Affiliated Lianyungang hospital of Xuzhou Medical University between November 2019 to April 2020 were selected as the case group and 30 healthy subjects in the same period were selected as the control group for the prospective study. The left ventricular end-diastolic volume (LVEDV), left ventricular end-systolic volume (LVESV) and left ventricular ejection fraction (LVEF) were calculated by modified biplane Simpson method. The left ventricular global longitudinal strain (GLS) was measured using two-dimensional speckle tracking echocardiography（2D-STE）myocardial automated functional imaging (AFI). The left ventricular global myocardial work index (GWI), global myocardial constructive work (GCW), global myocardial wasted work (GWW) and global myocardial work effificiency (GWE) were assessed by non-invasive LV-PSL , and to compare the differences and changes of parameters between the control group and the case group before and 3 days after surgery. Results: Compared with the control group, the LVEDV, LVESV and GWW of the case group were significantly increased before and 3 days after PCI (P < 0.05), and the LVEF, GLS, GWI, GCW and GWE were significantly decreased (P < 0.05); compared with the pre-PCI group, the GWW was significantly decreased and GWE was significantly increased 3 days after PCI (all P < 0.05), while the LVEDV, LVESV, LVEF, GLS, GWI and GCW had no significant changes (P > 0.05). GWI, GCW, GWW, GWE were significantly correlated with LVEF and GLS (P = 0.00). Conclusion: Non-invasive LV-PSL technology can be used to quantitatively evaluate left ventricular myocardial work in CAD patients before and after PCI, and provide a new method to accurately evaluate the effect of CAD on myocardial function and the recovery effect of myocardial function in the short term post-PCI.