The present invention is to provide a card insert/eject mechanism, which includes an insulating seat formed with a receiving space and a track groove; a metal housing covering the receiving space and track groove and having a position-limiting resilient plate at a bottom surface thereof; a sliding block slidable along the track groove and laterally provided with a pushing portion that extends into the receiving space thereby, when an electronic card pushes the pushing portion, the sliding block is moved against rear end of the insulating seat; a resilient element provided in the track groove for applying a force to rear end of the sliding block; and a release bar disposed in the track groove for releasing the position-limiting resilient plate and enabling the sliding block to push the electronic card out of the receiving space, so as to effectively solve the insecure card engagement problem in conventional push-push connectors.