The study of core@shell magnetic nanoparticles has a wide range of applications because of the unique combination of the nanoscale magnetic core and the functional shell. This report highlights some of the recent findings in the investigation of the synthesis, characterization and application of one important class of core@shell magnetic nanoparticles, i.e., magnetic nanoparticles coated with a gold shell (MNP@Au). The gold shell imparts the magnetic nanoparticles with many intriguing functional properties. Areas specifically highlighted in this report include strategies for the synthesis of MNP@Au nanoparticles, characterization of the core@shell nanostructures, and exploration of potential applications of the core@shell nanomaterials in terms of biological and catalytic interfacial reactivities. Implications of some of the research findings to address both fundamental and practical issues are also briefly discussed in an effort to further broaden the rapidly-emerging field of core@shell magnetic nanoparticles.