MULTILAYER WIRING BOARD

PROBLEM TO BE SOLVED: To provide a high density multilayer wiring board capable of reducing production man-hours and lead time.SOLUTION: A multilayer wiring board comprises: a core substrate (3) on which an interlayer connection (8) between wiring layers L5, L6(2) formed on both surfaces of an insulation layer via a through hole connecting their wiring layers L5, L6(2), is formed thereon; an insulation layer (4) and wiring layers L4, L7(2) formed on wiring layers L5, L6(2) on a lower layer side and an upper layer side of the core substrate (3), respectively; and interlayer connections (10) arranged on an upper and lower of the interlayer connection (8) of the core substrate (3), and formed by a non-through hole reaching on the interlayer connection (8) formed by a through hole passing from the wiring layer (2) to the insulation layer (4). The interlayer connection (10) formed by the non-through hole has a tapered shape in which a diameter decreases towards the interlayer connection (8) formed by the through hole of the core substrate (3) from wiring layers L4, L7(2).