An ultrasonic imaging apparatus includes an ultrasonic probe, a volume data generator to generate a plurality of volume data corresponding to echo signals received as the ultrasonic probe transmits the ultrasonic signals to the object a plurality of times before and while external stress is applied to the object, an elasticity data generator to generate elasticity data based on displacement of the plurality of volume data, a controller to adjust parameters of volume rendering using the elasticity data, and an image processor to perform the volume rendering using the adjusted parameters and generate a volume-rendered image.Accordingly, a multi-dimensional ultrasonic image of a target region of an object to be diagnosed in which lesion areas are separated from non-lesion tissues may be output. Thus, the information regarding the surface of the target region and the inside volume of the target region may be acquired.
