To provide a copper alloy foil with small surface roughness, and a high electroconductivity and strength, which has adequate adhesiveness to an adhesive containing an epoxy resin without being roughened, and can be laminated to be a copper-clad laminate, in a three-layer flexible substrate.

The copper alloy foil for laminate is characterized by employing a copper alloy containing specific elements, and making the thickness of a rust preventive film to be 3 nm or less from the surface, to give the surface adequate adhesiveness to the adhesive containing the epoxy resin, surface roughness of 2 μm or less by ten-points average surface roughness (Rz), and 180-degree peel strength of 8.0 N/cm or more when bonded to a substrate film with the adhesive containing the epoxy resin, without being roughened.