Abstract: Objective To assess the characteristics of left ventricle vortex flow in patients with dilated cardiomyopathy (DCM) using the vectorial flow imaging(VFM). Methods Forty healthy persons served as a control group and 20 DCM patients served as study group in this study. They underwent conventional echocardiography and VFM. Their images were analyzed. Evolution rules of their left ventricle vortex flow were observed. Different vortex flow parameters were quantitatively assessed and analyzed. Results More changes of vortex flow morphology and locations occurred in study group than in control group. The Q_max, semi radius area (S)and radius (s) of vortex flow were significantly larger while its Q_max/S was significantly lower in study group than in control group(15.27±7.92 vs 24.21±10.62, P< 0.01). The Q_max/S was positively related with LVEF (r=0.417, P=0.000). Conclusion The evolution rules of left ventricle vortex flow are similar between DCM patients and normal controls, but the vortex flow is greater in DCM patients than in controls. Q_max/S may be used as a new index for the assessment of left ventricular systolic function.