A screen data transmitting device for transmitting screen data to a screen display terminal through a network. A generation device generates a display image data. A storage device stores compression properties information associating a plurality of compression schemes with a plurality of classes of graphical user interface (GUI) components. A selection device selects one of the compression schemes with respect to a GUI component that is present in a region of the display image data. A compression device compresses the region of the display image data according to the selected compression scheme. Then, a transmission device transmits the screen data including the compressed display image data to the screen display terminal.