Deterioration of the image quality of a moving image which is deteriorated due to a motion-compensated frame rate conversion (FRC) processing is prevented. An image display device comprises an FRC portion (10) for converting the number of frames of an input image signal by interpolating an image signal to which the motion compensation processing is performed between frames of the input image signal and a controlling portion (15) for controlling the operation of the FRC portion (10) after determining whether or not the degree of deterioration of the input image signal is equal to or higher than a predetermined value. The FRC portion (10) comprises a motion vector detecting portion (11e) for detecting a motion vector between frames of the input image signal, an interpolating vector evaluating portion (11f) for allocating an interpolating vector between the frames based on the motion vector information, and an interpolating frame generating portion (12d) for generating an interpolating frame from the interpolating vector. If the degree of deterioration of the input image signal is equal to or higher than a predetermined value, the controlling portion (15) makes the motion compensation of the FRC portion (10) ineffective by setting the motion vector detected by the motion vector detecting portion (11e) to a zero vector.