Abstract: Developments of many cardiovascular problems have been shown to have a close relationship with arterial flow conditions.However,current ultrasound/Doppler imaging techniques cannot resolve the complex nature of arterial blood flow.We have recently developed a novel contrast-based echo particle imaging technique(Echo PIV) without angel dependence for noninvasive measuring multi-component flow vectors.Here we introduce the Echo PIV principles,system characterization and utility examination for characterizing hemodynamics in laminar flow and rotating flow.Echo PIV measurement results show its capability to resolve the complex hemodynamics including proximal flow velocity vectors, and velocity mapping.The Echo PIV method provides an easy,direct and accurate means of quantitatively yet noninvasively characterizing the complex vascular hemodynamics.