An ultrasound diagnosis system, a medical image display apparatus and displaying method that simultaneously acquires virtual endoscopy image data and multi-planar-reconstruction (MPR) image data of a diagnosing target region based on the volume data acquired from an object. Virtual endoscopy image data is generated by setting up a viewing point and a viewing direction on a volume data acquired from the object. A marker is provided on a target region of a lumen organ shown in the virtual endoscopy image data for setting up an observing direction. A reference line started from the volume data is set up along an observing direction. By comparing a voxel value of the volume data that is crossing to the reference line with a prescribed threshold value, a reference point where a surface of the diagnosing target region crosses the reference line is set up to the volume data. MPR image data is generated by extracting each voxel of the volume data corresponded to each of three MPR cross-sectional planes that are mutually orthogonally crossing at the reference point and displayed with the virtual endoscopy image data.
