According to the results of magnetotelluric sounding under ore bodies of Ozernoe pyrite- polymetallic deposit revealed a linear zone of low resistivity rocks, which can be traced to a depth of 10 km and can be regarded as structure of feeder fluid. The presence of deep roots in pyrite ore deposits of the Ozernoe deposit is not consistent with existing understanding of its affinity to outliers Early Paleozoic volcanic-sedimentary rocks in the sag of the roof of the Angara-Vitim batholith.