To provide a card game device that presents a question to a user by displaying an image while changing the sharpness thereof.

The card game device includes a case provided with a card housing space for housing a card having an answer image displayed on the surface and provided with a first window for viewing the answer image of the card housed in the card housing space. A device body includes: a light diffusing plate which faces the surface of the card housed in the card housing space, is movable in a direction relatively separating from or approaching the surface of the card, and changes the visibility of the answer image through the first viewing window in accordance with a distance from the surface of the card; and a visibility adjusting means for changing the visibility by changing a distance between the surface of the card housed in the card housing space and the light diffusing plate gradually or stepwise.