Nanoheterostructures (NHSs) that combine various nanomaterials into one entity have received an extensive amount of attention in current research. The enhanced performance of the NHSs over their individual constituents have arisen from their unique electronic structure. To rationally synthesize NHSs, two issues need to be addressed. The first issue that should be explored is the mechanism by which the disparate components are integrated into the main structure. The second issue is the relationship between the NHS and its corresponding properties. In this review article, we will focus on these two issues from the perspectives of both experimental and theoretical methodologies.