An electrical connector (100) for electrically connecting a Central Processing Unit (CPU) with a Printed Circuit Board (PCB), includes a base (2), a plurality of insulative layers (34), a plurality of contacts (4) and a plurality of cams (33). The base defines a cavity (21) and the insulative layers are stacked and received in the cavity. The insulative layers define a plurality of passageways therein. The contacts are received in the passageways of the insulative layers. The cams are rotatable around to push different insulative layers to have different degrees of movement in a predetermined direction.