Objective To investigate the application value of the transesophageal echocardiography TEE in patients with nonvalvular atrial fibrillation about the size lobes morphology and function of left atrial appendage LAA Methods One hundred and forty-two patients underwent TEE were divided into nonvalvular atrial fibrillation group 98 cases and non atrial fibrillation group 44 cases The orifice diameter depth volume peak emptying velocity PEV of the LAA and the 1 eft atrial dimension LAD were measured The form and lobes of LAA thrombus and spontaneous echo contrast SEC in LAA were observed Results The LAA orifice diameter depth volume and LAD of patients with atrial fibrillation were significantly higher than those in the group without atrial fibrillation which showed statistical significance P < 0 05 Forty-one cases in atrial fibrillation group were found with the SEC and the number with thrombus in LAA was 22 The differences of PEV between chicken wings and non-chicken wings were statistically significant P <0 05 The SEC in LAA and the lobe number of LAA had no relevance Conclusions It was reliable to analyze the size morphologies lobes and hemodynamic parameters of LAA in patients with atrial fibrillation by TEE which provided reference for percutaneous LAA occlusion and anticoagulation therapy for the patients with atrial fibrillation.