The present invention discloses a structure for sharing card slot space. The structure includes a housing. A first card slot and a second card slot are disposed inside the housing. The insertion port of the first card slot is disposed opposite the insertion port of the second card slot. A common space is disposed between the first card slot and the second card slot. A groove is disposed inside the housing of the common space. A stopper is disposed inside the groove. The stopper can slide in the groove between the first card slot and the second card slot and is configured to prevent a card corresponding to the second card slot from being inserted into the first card slot or to prevent a card corresponding to the first card slot from being inserted into the second card slot.