A card edge connector (100) for use with an electronic card (100) includes an elongated housing (1) having a pair of opposited side walls (10), a central slot (11) between the side walls (10), and a holding portion (12) at one end thereof. The holding portion (12) defining at least one leading hole (126) extending along a length direction of the housing (1). A retainer (3) is movably retained in the holding portion (12). The retainer (3) has a body portion (31) with a positioning post (315) received in the leading hole (126), a latch projection (12) protruding inwardly from the body portion (31) for locking the electronic card (200). Wherein the positioning post (315) is movable in the leading hole (126) along the length direction so as to prevent the retainer (3) from being separated from the holding portion (12).