Background Atrial fibrillation (AF) is common in chronic obstructive pulmonary disease (COPD) patients. It is known that impaired forced expiratory volume in 1 s (FEV1) is one of the risk factors of cardiovascular disease. Two-dimensional speckle tracking echocardiography (2D-STE) can detect deterioration of left atrial mechanical functions in the subclinical stage. We hypothesized that reduced lung functions, measured by FEV1 in COPD patients, may be associated with impaired left atrial (LA) mechanical functions. Objectives Present study included 127 consecutive COPD patients. We divided study population into two groups: patients with normal LA strain (n = 20) or with impaired LA strain (n = 107). Results In univariate logistic regression analysis, age (p: 0.001), FEV1% (p < 0.001), FEV1 (p < 0.001), FEV1/forced vital capacity (FVC) (p: 0.014), white blood cell (p: 0.012), LA Max vol (p: 0.026), C-reactive protein (p :0.001), arterial oxygen pressure (PaO2) (p: 0.019), arterial oxygen saturation (SO2) (p: 0.021), left ventricle ejection fraction (LVEF) (p: 0.042), and mitral A-wave velocity (p: 0.017) were associated with impaired LA-strain. In multivariate logistic regression analysis, age (p: 0.043), FEV1 (p < 0.001), LA Max vol (p: 0.004), and LVEF (p: 0.004) were independently associated with impaired LA strain. Conclusion FEV1 is associated with impaired left atrial strain independently of arterial blood gas and left ventricular diastolic dysfunction parameters in COPD patients with preserved left ventricular systolic function.