Objective To evaluate the relationship between pattern of left ventricular dilation and functional mitral regurgitation (FMR) by echocardiography. Methods A single-center retrospective observational study was conducted on 117 patients with age of 31-77 years and left ventricular end diastolic dimension≥60 mm treated in our hospital from January 2013 through May 2016. These patients were divided into four groups by FMR degree: FMR-None/Trace (FMR-N/T group,n=33), FMR-Minor (FMR-Mi group,n=37), FMR-Moderate (FMR-Mo group,n=34) and FMR-Severe (FMR-Se group,n=13). We analyzed their basic information and echocardiographic parameters including left ventricular dimension, volume, systolic function, spherical index, regional wall motion score index, tenting height and area of mitral vavle as well as anterior/posterior angle. Results The incidences of inferior/posterior/lateral myocardial infarction and basal myocardial dyskinesia/aneurysm increased with the increase of FMR degree (FMR-N/T vs. FMR-Mi vs. FMR-Mo vs. FMR-Se: 12.1% vs. 18.9% vs. 44.1% vs. 46.2%,P=0.001 and 12.1% vs. 27.0% vs.47.1% vs. 53.8%,P=0.005, respectively). The tenting height and area of mitral valve, anterior/posterior angle, regional wall score index of the left ventricle where the papillary muscle was attached to had a positive correlation with FMR degree (P＜0.05). Conclusion There is a relationship between regional left ventricular dilation and FMR. Evaluating and improving those parameters is very important when we choose the treatment strategy of functional mitral regurgitaion.