(Currently amended) A current measurement device comprising: a conductor in which a to-be-measured current flows; a base including a placement surface on which the conductor is disposed; a pair of detection coils (120a, 120b) having the same configuration such that absolute values of inductive voltage signals generated in said detection coils (120a, 120b) by an external magnetic field that is magnetic noise are the same; said pair of detection coils (120a, 120b) being connected in series and in opposite polarity with respect to each other, and disposed on the placement surface of the base such that the conductor is positioned between the pair of detection coils (120a, 120b), and each detection coil of the pair of detection coils (120a, 120b) is spaced from the conductor by an insulating distance; and a calculator configured to calculate a value of the to-be-measured current based on an inductive voltage signal from the pair of detection coils (120a, 120b), wherein the conductor has a height longer than a width of the conductor, the height being perpendicular to the placement surface, the width being in a direction orthogonal to a direction of conduction of the conductor, each coil of the pair of detection coils (120a, 120b) has a winding height that is in the same direction as the height of the conductor, the conductor has a shape surrounding an outer circumference of one detection coil (120a, 120b) of the pair of detection coils (120a, 120b), said one detection coil (120a, 120b) has a circular cross-section, and the other detection coil (120b, 120a) of the pair of detection coils (120a, 120b) has a rectangular-shaped cross-section having a long side parallel to the direction of conduction of the conductor, or a square-shaped cross-section having a side parallel to the direction of conduction of the conductor. a conductor in which a to-be-measured current flows; a base including a placement surface on which the conductor is disposed; a pair of detection coils (120a, 120b) having the same configuration such that absolute values of inductive voltage signals generated in said detection coils (120a, 120b) by an external magnetic field that is magnetic noise are the same; said pair of detection coils (120a, 120b) being connected in series and in opposite polarity with respect to each other, and disposed on the placement surface of the base such that the conductor is positioned between the pair of detection coils (120a, 120b), and each detection coil of the pair of detection coils (120a, 120b) is spaced from the conductor by an insulating distance; and a calculator configured to calculate a value of the to-be-measured current based on an inductive voltage signal from the pair of detection coils (120a, 120b), wherein the conductor has a height longer than a width of the conductor, the height being perpendicular to the placement surface, the width being in a direction orthogonal to a direction of conduction of the conductor, each coil of the pair of detection coils (120a, 120b) has a winding height that is in the same direction as the height of the conductor, the conductor has a shape surrounding an outer circumference of one detection coil (120a, 120b) of the pair of detection coils (120a, 120b), said one detection coil (120a, 120b) has a circular cross-section, and the other detection coil (120b, 120a) of the pair of detection coils (120a, 120b) has a rectangular-shaped cross-section having a long side parallel to the direction of conduction of the conductor, or a square-shaped cross-section having a side parallel to the direction of conduction of the conductor.