A split-type display system includes a processing device, a display device, and a transmission cable connecting the devices. The processing device includes a processing unit and a low-to-high unit. The processing unit generates a first image signal having both a first transmission rate and a first channel number. The low-to-high unit converts the first image signal into a second image signal having both a second transmission rate and a second channel number. The first transmission rate is lower than the second transmission rate. The display device includes a high-to-low unit and a display unit. The high-to-low unit receives and converts the second image signal into a third image signal having both a third transmission rate and a third channel number. The display unit displays the third image signal. a number of channels of the transmission cable is the same as the second channel number.