For the purpose of synthesizing 2D-Material–Magnetic nanocomposites, several new modifications of existing 2D-materials synthesis methods by exfoliation and chemical synthesis from liquid charge are developed. Using them, graphene (G), graphene oxide (GO), reduced graphene oxide (rGO) and hexagonal boron nitride (h-BN) matrix magnetic nanocomposites for the first time are obtained by coating or intercalation their nanoparticles with ferromagnetic iron (Fe) or ferrimagnetic iron oxide – magnetite (Fe3O4). These materials are prospective for variety of high tech applications. In particular, h-BN–Fe3O4 composite nanoparticles can serve for neutron-capturing boron isotope 10B effective delivery agents in BNCT (Boron Neutron Capture Therapy) of cancer as they allow the controlling by an external magnetic field targeting to tumor tissue.