A laminated wiring board comprising: a first wiring board forming wiring
layers on the upper surface and on the lower surface of a first ceramic
insulated substrate; and a second wiring board forming wiring layers on
the upper surface and on the lower surface of a second ceramic insulated
substrate; the wiring layer on the lower surface of the first wiring
board and the wiring layer on the upper surface of the second wiring
board being connected together through connecting electrodes; wherein a
coefficient .alpha..sub.1 of thermal expansion of the first ceramic
insulated substrate at 0 to 150.degree. C. and a coefficient
.alpha..sub.2 of thermal expansion of the second ceramic insulated
substrate at 0 to 150.degree. C. are satisfying the following conditions:
.alpha..sub.1<.alpha..sub.2
.alpha..sub.2-.alpha..sub.1.ltoreq.9.times.10.sup.-6/.degree. C. The
laminated wiring board offers a high degree of mounting reliability even
when it is interposed between the electric device such as a silicon
semiconductor device having a small coefficient of thermal expansion and
an external circuit board such as a printed board having a large
coefficient of thermal expansion.