As a consequence of the relative motion between the fine charged dust in Saturn's F-ring and the surrounding plasma, it is estimated that this ring carries a current of over 105 A. It is shown that such a current can alter the magnetospheric field morphology in the vicinity of the ring to an extent which could be detected by a spacecraft at a height of over 100 km above the ring plane. This in principle provides a method of estimating the dust ring current and consequently the grain charge. Some consequences of this novel current in the stability of the dust ring are briefly discussed.