An electrical connector includes a base, an upper cover, terminals and a lever. The base is formed with terminal slots and a supporting seat formed with pivoting portions. The upper cover has a main body formed with through holes for accommodating the terminals, and a rear plate connected to a rear end of the main body. The lever has a rocking portion and a pivoting shaft, which includes first shafts pivotally connected to the pivoting portions, and a second shaft engaged with the rear plate. A side edge of the rear plate is nearer to a middle of the upper cover than a side edge of the main body. The rocking portion is disposed between the side edges so that the rocking portion may be rotated with respect to the side edge of the rear plate without exceeding the side edge of the main body.