The present invention relates to a socket assembly for testing semiconductor device comprising a socket board electrically connected to an outside testing device wherein a plurality of connection pins connected to leads of a semiconductor is provided; a socket guide mounted to cover the socket board, with an open part formed so that the semiconductor may in/out, thereby connecting the semiconductor to the connection pins of the socket board; and a spacer interposed between the socket board and the socket guide for maintaining a predetermined distance between the semiconductor and the socket board by touching an surface of the semiconductor having moved into an inside of the socket guide before a surface of each carrier touches the socket guide. According to the present invention, the balls or the leads of each semiconductor may be pressed to the connection pins of the socket in a predetermined depth without replacing the carriers though the semiconductors have the different thicknesses.