Objective To evaluate the left ventricular regional systolic function before and after left anterior descending coronary artery stent implantation (PCI) using three-dimensional speckle tracking imaging (3D-STI) in patients with coronary artery disease. Methods 30 patients who received left anterior descending PCl were underwent routine and three-dimensional echocardiography before and after 3~5 days, 3 months to obtain longitudinal strain(LS), radial strain(RS), circumferential strain(CS)and area strain(AS) of the seven myocardial segments(BA,BAS,MA,MAS,AA,AS,A ),which accepted blood from the left anterior descending coronary artery. We analyzed the changes of the parameters before and after the coronary stent implantation. Results The 5/7 segment of the longitudinal strain(BA,MA,BAS,MAS,AA), 3/7 segment of area strain(BA,MA,MAS), 3/7 segment of circumferential strain (BA,BAS,MA)and 2/7 segment of radial strain (BAS,MAS)at 3~5 days after PCI were higher than that before the operation. The difference was statistically significant (P＜ 0.05). The longitudinal, circumferential, radial and area strain of the left anterior descending branch at 3 months after the operation were higher than that before and 3~5 days after the operation. The difference was statistically significant (P＜ 0.05). Conclusion 3D-STI may early evaluate the improvement of left ventricular regional systolic function before and after coronary artery PCI treatment in patients with coronary heart disease, and provide a basis for early clinical evaluation of PCI effect and follow-up treatment.