Objective Evaluate the left ventricular diastolic function in patients with coronary artery disease by three-dimensional speckle tracking imaging Methods 66 patients with coronary artery disease were selected，according to left ventricular end-diastolic pressure (LVEDP), they were divided into two groups: 31 cases in the group with normal left ventricular diastolic function, LVEDP ≤ 15mmhg; 35 cases in the group with left ventricular diastolic dysfunction, LVEDP > 15mmhg. 30 healthy volunteers were selected as the control group. The longitudinal strain (LS), circumferential strain (CS), area strain (AS) and radial strain (RS) of 17 segments of left ventricular were obtained by 4D auto LVQ software. Results Four strains of diseased myocardium in left ventricular diastolic dysfunction group was significantly lower than those in normal left ventricular diastolic function group and control group (P < 0.05)，LS and AS of diseased myocardium in normal left ventricular diastolic function group were lower than those in control group (P < 0.05). Pearson correlation analysis showed that the four strains had good correlation with LVEDP: LS (r = 0.777, P < 0.001), CS (r = 0.713, P < 0.001), AS (r = 0.803, P < 0.001), RS (r = -0.719, P < 0.001). Receiver operator characteristic (ROC) curve analysis showed that the area under the curve (AUC) of four groups of strains (LS, CS, AS and RS) which predicted left ventricular diastolic dysfunction were 0.76, 0.76, 0.86 and 0.72 ,P <0.001. Conclusions Three-dimensional speckle tracking imaging can be used to evaluate left ventricular diastolic function in patients with coronary artery disease. LS and AS are more useful to find early left ventricular diastolic dysfunction.