The present disclosure provides an ultrasound flow imaging method and ultrasound imaging system. The system may include a probe, a transmitting circuit which may excite the probe to transmit volume ultrasound beams to the scanning target, a receiving circuit 4, and a beam forming unit which may receive the echoes of the volume ultrasound beams and obtain the volume ultrasound echo signals, a data processing unit which may obtain the flow velocity vector information of the target point in the scanning target and the three-dimensional ultrasound image data based on the volume ultrasound echo signals, and a stereoscopic display device which may display the three-dimensional ultrasound image data to form the spatial stereoscopic image of the scanning target and superimposes the flow velocity vector information in the spatial stereoscopic image.