Objective To investigate the correlation between the left atrial appendage emptying flow velocity (LAAFV) and the left atrial function parameters in patients with non-valvular atrial fibrillation and sinus rhythm respectively, exploring the valuable non-interventional ultrasound parameters for left atrial appendage hemodynamic status. Methods 110 patients who presented to our hospital for atrial fibrillation or dizziness were selected. They all completed transthoracic echocardiography (TTE) and transesophageal echocardiography (TEE) at the same time. The patients were divided into sinus rhythm group and atrial fibrillation group according to their heart rhythm. The clinical characteristics were recorded. Left atrial diameters in different views, left atrial maximum volume, left ventricular internal dimension diastole and left ventricular ejection fraction were recorded. Speckle tracking technique was applied to obtain left atrial strain during reservoir phase, conduit phase, contraction phase and left ventricular global longitudinal strain. Left atrial appendage emptying flow velocity was gained from TEE. The differences of the observed parameters between the two groups were compared. Pearson correlation analysis was used to explore the correlation between the left atrial structural and functional parameters by TTE and LAAFV by TEE in the two groups respectively. Results 90 patients were finally included in the study, 60 were in sinus rhythm group and 30 in non-valvular atrial fibrillation group. There was no significant difference in gender or BMI between the two groups. The mean age in atrial fibrillation group was (67.40±6.87) years, significantly greater than that in sinus rhythm group ((40.03±13.47)years, p<0.05); the differences in left ventricular ejection fraction(61.83±5.87%vs.65.94±6.20%), left ventricular global longitudinal strain(-17.37±4.09%vs.-21.71±2.20%), left atrial maximum volume(68.83±22.84mlvs. 40.28±12.17ml), left atrial strain during reservoir phase (15.53±9.41%vs. 34.91±7.15%), conduit phase (-9.66±5.10%vs.-19.97±7.03%)and contraction phase(-6.07±6.22%vs. -14.72±4.74%)were all statistically significant (p<0.05). In correlation analysis, there was a significant positive correlation between left atrial emptying flow rate and left atrial strain during contraction phase in both groups (p<0.05), with r values of 0.63 in sinus rhythm group and 0.62 in atrial fibrillation heart rate group. Conclusion Patients with non-valvular atrial fibrillation may have altered left atrial morphology and function, but left atrial appendage emptying flow rate is positively correlated with left atrial contraction function in both non-valvular atrial fibrillation and sinus rhythm, and they are with the same extent.