To prepare an insulating adhesive film having excellent flexibility without lowering the glass transition temperature, a multi-layer printed-wiring board using the same and its manufacturing method.

The multi-layer printed-wiring board is composed of an insulating adhesive film comprising a polyfunctional epoxy resin having three or more functional groups, a difunctional epoxy resin which is liquid at 25°C and, simultaneously, has a viscosity of ≤100 P, and an acrylonitrile butadiene rubber, an inner circuit substrate having an inner circuit, an insulating layer on the inner circuit substrate, an outer circuit formed on the surface of the insulating layer, and a via hole connecting the inner circuit with the outer circuit, The method of manufacturing the multi-layer printed-wiring board comprises laminating a printed-wiring board constituted of an insulating adhesive film to form an insulating layer on an inner circuit substrate having an inner circuit to effect adhesion with the insulating layer, making a via hole reaching the inner circuit, forming an outer layer circuit on the surface of the insulating adhesive film, and effecting electrical connection between the outer circuit and the inner circuit.