A card connector comprising a connector housing (30) where formed are a pair of grooves (50a), (50b) for guiding the insertion/removal of first and second cards while supporting both sides of an upper body part (21) of the first thick card (20) and both sides of a card body (11) of the second thin card (10), and a sidewall (60) defining a space for housing therein a lower body part (23) of the first card (20) in the lower portion of the space defined by the pair of grooves (50a), (50b), whereby the elastic displacements of the contact terminals (40) are the same when either the first or second card is inserted.