The present invention provides a quantum dot display device and a manufacturing method thereof. The quantum dot display device includes a base substrate, a backlight, a color conversion layer disposed on a side of the backlight away from the base substrate, and an electro-fluidic shutter disposed on a side of the color conversion layer away from the backlight. The electro-fluidic shutter includes a plurality of shutter units, and a sealing portion is disposed between adjacent shutter units. Contrast of the quantum dot display device under strong ambient light is improved, which is beneficial for application in outdoor advertising displays and the like.