The world market offers the greater nomenclature of the facilities for measuring parameters of electrosafety, as there is always a demand on them. The majorities of facilities do not guarantee accuracy or in general cannot value the measured parameter unless they do execute requirements and conditions of their operation. In particular, measurement of the resistance grounding device (GD), at resistivity of the soil more than 500 Ohm.m and in large concourse of the underground communication (seaports) requires the high qualification of the operator and large number of measurements. For instance, in the article unpinned way of measurements GD is considered based on measurement of phase voltages of network with deafgrounded of neutrality in connection with the investigation sidebar of the grounding device contour. The Offered way of the determination of the resistance GD, in basic range (0.1-10 Ohm) allows to value the garbled resistance GD with necessary accuracy.