Abstract: In a process and device for measuring the specific capacity of an electric cable by means of a cylindrical measuring electrode through which the cable is passed and between which and the cable conductor an alternating voltage is maintained, the capacitative current flowing between the cable conductor and a defined length of the electrode is determined by measurement of the currents flowing in the cable conductor at respective points located adjacent the ends of the defined length of the electrode, and obtaining the difference between the currents. This avoids the need for direct measurement of the capacitative current and thus enables screening electrodes at each end of the measuring electrode to be directly electrically connected to or integral with the measuring electrode so that they can be maintained at the same potential as the measuring electrode without the need for special electrical circuitry.