1. A medical image processing apparatus which processes a medical image generated from three-dimensional volume data showing gradation at a plurality of coordinates indicating an inside of a living body and comprises: a display control unit which has a plurality of display regions and displays said medical image in said display regions; a reception unit which accepts designation of an arbitrary point on said medical image; a coordinate specifying unit which specifies coordinates indicating a position in the three-dimensional volume data of said point designated by the acceptance; and a region specifying unit which specifies a closed region inside the living body which is expressed by the three-dimensional volume data and which contains said designated point; the position in the three-dimensional volume data of said point designated specified by said coordinate specifying unit in association with each other, and wherein said region specifying unit calculates with said information recorded by said recording unit and said three-dimensional volume data, and specifies the contour of said closed region containing said designated point.