In recent years, theranostics have received enormous attention for their use in individualized diagnosis and treatment. The ability of viral coat protein subunits to assemble hierarchically can be used to package various kinds of foreign compounds. Moreover, numerous chemistries and modification strategies allow the functionalization of these virus-like particles (VLPs) with imaging reagents, targeting ligands, or therapeutic molecules. VLP nanoplatforms have great potential utility in the design of sophisticated multifunctional theranostic platforms. Numerous studies have reported the construction of multifunctional nanoparticles using VLPs for targeted diagnoses and treatment. In this paper, the latest progress in molecular imaging, drug delivery, and multifunctional theranostic nanodevices based on VLPs is reviewed.