PURPOSE: To achieve a higher efficiency of the measuring work with voltage and current detection elements integrated by positioning an electrode with a circular arc cross section, a spacer and a shield layer of a conductor made of a magnetic material on a concentric circle of a wire to be measured.

CONSTITUTION: As electrode plate 4 with a circular arc cross section, a spacer 5 and a shield layer 6 of a conductor made of a magnetic material are positioned at a fixed interval on a concentric circle of a wire 1 inside a body 3 of a voltage/current sensor comprizing an insulator so build in an upper/lower half- split construction to grasp a wire 1 to be measured with a wire cover layer 2 in the center thereof. A voltage wire 8 is connected to an electrode plate 4 while an earth wire 9 to the layer 6 to measure a voltage alone induced by the voltage applied to the wire 1 being measured. The layer 6 is wound with a coil 7 to construct a current transformer, which measures current.