Disclosed are an ultrasound imaging apparatus which includes a 3D display to display a 3D ultrasound image as well as a 2D display to display a 2D ultrasound image, thereby displaying both the anatomical shape of a diagnosis part and a high-resolution image, and a control method thereof. The ultrasound imaging apparatus includes an ultrasound data acquirer configured to acquire ultrasound data, a volume data generator configured to generate volume data based on the ultrasound data, a 3-Dimensional (3D) display image generator configured to generate a 3D ultrasound image based on the volume data, a cross-sectional image acquirer configured to acquire a cross-sectional image based on the volume data, a 3D display configured to display the 3D ultrasound image, and a 2D display configured to display the cross-sectional image.