Provided is a technique to confirm the performance of the conductive resin layer of a current collector without actually preparing an electrode structure, a non-aqueous electrolyte battery, an electrical double layer capacitor, a lithium ion capacitor, or an electrical storage device, and to confirm the performance of the conductive resin layer easily with high accuracy by a non-destructive test. A current collector includes a conductive substrate and a resin layer possessing conductivity, the resin layer being formed on at least one side of the conductive substrate. The resin layer possessing conductivity contains a resin and a conductive material containing carbon as a main component. When the color tone of the surface of the resin layer possessing conductivity is specified with L*a*b* color system, L* is 60 or lower, a* is −1.0 to 1.0, and b* is −1.0 to 3.0.