An image displaying apparatus and method thereof for displaying on a monitor an original image generated based on image data of an object acquired through an image radiography apparatus together with posture data for the original image that is acquired at a radiography time. The image displaying apparatus and method includes a function unit and/or a function configured to rotate the original image centering on an axis in order to dissolve a displacement between a first (reference) posture data that is acquired based on the image radiography apparatus and/or a bed unit for supporting the object, and actual posture of the original image. The function unit further displays a second (actual) posture data that is acquired by the rotation of the original image by replacing the first (reference) posture data.