The materials of magnetic observations allow us to consider a number of new questions about the geological structure of the Kola Peninsula and the location of a number of minerals.On the maps of magnetic field plots of the AT, a large number of anomalies and anomalous zones, different in size, shape, intensity and character of the field, were identified. The geological nature of many of them is not in doubt and is easily established by comparing the magnetic field maps with detailed geological maps made on the basis of the study of the day surface and shallow excavations. Such material is insufficient for deciphering anomalies with more complex nature. These anomalies reflect the properties and composition of rocks both partially exposed on the day surface of the crystalline basement and magnetic masses embedded in the basement rocks, or are caused only by the latter. As usual, they are also divided into regional and local.