It is to provide a wiring board for a semiconductor integrated circuit
package, which exhibits an excellent signal property and a high effect
for decreasing the switching noise at the time of mounting an LSI of an
area-array structure. In a multilayer wiring board for a package, which
comprises, on a wiring layer of an LSI chip mount surface, a ground pad,
a power supply pad, and a signal pad for mounting LSI chip, and a ground
plane that extends around a group of those pads, the ground pad disposed
on the inner side, among the above-described pads, is connected to the
ground plane that surrounds the pad group through a connecting wiring.