Investigations of geoelectric structure of the Rybachy Peninsula located in the northern part of the Kola Peninsula (the Barents Sea shore) have been carried out by the audiomagnetotelluric (AMT) sounding method using a new technology with ungrounded lines for electric field measurements. The deep structure of the Rybachy Peninsula up to 8-10 km was investigated, basement mapping and fault zones localization were fulfilled. The AMT results have allowed adjusting essentially the concept about the geological structure of the Rybachy Peninsula in comparison with data of previous seismic works. The AMT data about the basement depth were confirmed by the subsequent drilling.