An image display device comprises a first clock generator for generating and outputting a first clock based on input horizontal synchronizing signals corresponding to horizontal lines making up input image signals, a second clock generator for generating and outputting a second clock, storage configured so as to accumulate image data sampled from the input image signals based on the first clock using the first clock output from the first clock generator and read out the accumulated image data using the second clock output from the second clock generator, a controller for outputting control signals for controlling the cycle of output horizontal synchronizing signals at the time of reading out and displaying the accumulated image data from the storage, according to image size information of the input image signals, cycle information of the input horizontal synchronizing signals, display panel size information, and cycle information of the second clock, and a synchronizing signal generator for outputting the output horizontal synchronizing signals based on the control signals output from the controller. Accordingly, image scaling processing can be performed properly at arbitrary conversion ratios.