This chapter presents an overview of the magnetic iron oxide- and gold-based nanocarriers which have been developed for brain drug delivery. The efficient delivery of drugs to the brain remains a challenge because of the extremely low permeability and selective nature of the blood-brain barrier. Magnetite nanoparticles exhibit unique size-dependent magnetic properties. Bulk magnetite is a ferrimagnetic material composed of multiple magnetic domains. The application of an external alternating magnetic field to magnetic iron oxide nanoparticles leads to the production of energy, in the form of heat, which leads to a local increase in the temperature. The design of inorganic nanocarriers for in vivo targeting applications is complex because it must take into account all the specifications required by the biological character of the application. Surface modification and bioconjugation of bare inorganic nanoparticles are necessary to make them suitable for various bioapplications.