A card connector (100) mounted on a printed circuit board to connect with an electronic element, includes an insulating housing (50) retaining a plurality of terminals (51), a shell (31) covering on the insulating housing to define a cavity (20) for receiving a card, the cavity defining a first portion (310) and a second portion (311), the first portion having a width greater than that of the second portion along a direction perpendicular to an inserting direction of the card, a void space (34) located at a lateral side of the second portion, and at a front of the first portion, and a mating connector (14) mounted on the printed circuit board and located at the void space for connecting the card connector with the electronic element electrically.