The present invention provides a carrier-attached copper foil, wherein an ultrathin copper foil is not peeled from the carrier prior to the lamination to an insulating substrate, but can be peeled from the carrier after the lamination to the insulating substrate. A carrier-attached copper foil comprising a copper foil carrier, an intermediate layer laminated on the copper foil carrier, and an ultrathin copper layer laminated on the intermediate layer, wherein the intermediate foil is configured with a Ni layer in contact with an interface of the copper foil carrier and a Cr layer in contact with an interface of the ultrathin copper layer, said Ni layer containing 1,000-40,000 µg/dm 2 of Ni and said Cr layer containing 10-100 µg/dm 2 of Cr is provided.