In an electronic device, a slider is disposed in an insertion opening of a housing of a card edge connector. The slider is movable with an insertion operation of a circuit board into the insertion opening from an initial position before the circuit board is inserted to an insertion completed position where the insertion operation of the circuit board is completed by being pushed by the circuit board. When the slider is at the initial position, terminal projections are supported on a support surface of the slider in a resiliently deformed condition so that contacts are separated from an electrode-formed surface of the circuit board. When the slider is at the insertion completed position, the terminal projections are completely separated from the slider and in a state of applying a spring back force of resilient deformation to the circuit board through the contacts.