A display system and a control method are provided. The display system includes a display device, an illumination device and a control circuit. The display device includes a display panel. The display panel is configured to display an image frame. The illumination device is movably disposed on the display device. The illumination device selectively projects light in a first direction or in a second direction different from the first direction. When the illumination device projects the light in the first direction, the control circuit generates a first control signal so as to control the illumination device to perform a first illumination mode. When the illumination device projects the light in the second direction, the control circuit generates a second control signal so as to control the illumination device to perform a second illumination mode different from the first illumination mode.