A socket connector includes a socket body and a plurality of contact terminals received in the socket body. The socket body includes an upper surface, a plurality of sidewalls extending upwardly from the upper surface. The upper surface and the sidewalls jointly define a cavity for receiving an IC package therein. At least one of the sidewalls is provided with a resilient arm having two ends connected to the sidewall and a close-loop slot behind the resilient arm. The resilient arm is provided with a positioning member extending toward the cavity.