Provided is an ultrasound imaging apparatus comprising: an image processing unit for connecting relevant blood flows and classifying the same into a plurality of blood flow trees on the basis of information on blood flow direction and blood flow velocity obtained from morphological information of a target object and three-dimensional blood flow data; a user input unit for receiving a user input which selects a blood flow tree, in which a target blood flow is included, from among the plurality of blood flow trees; and a display unit for displaying the selected blood flow tree on a three-dimensional rendering image on the basis of the user input.