Significant progress has been made in the formulation of the functional nanomaterials with microemulsion phase. Microemulsion phase can be considered as true nanoreactors, which can be used to synthesize nanomaterials. Properties and the mechanism of nanoparticle formation with microemulsion phase are reviewed in this paper. Preparation of the various nanomaterials, such as metal nanomaterials, oxide nanomaterials, magnetic nanoparticles, inorganic and inorganic compounds nanomaterials, metallic-organic composite nanomaterials, and other composite nanomaterials, are investigated with different microemulsion phases. The possible formation mechanisms are presented with the schematic diagram. microemulsion phase, functional nanomaterials, surfactant, formation mechanism Citation: Li W, Xu P, Zhou H C, et al. Advanced functional nanomaterials with microemulsion phase.