We have successfully employed an oleate-modified nucleation/hydrothermal growth process for the synthesis of YVO4:Eu3+ nanoparticles. Oleate-passivated YVO4:Eu3+ nanoparticles, formed by precipitation of Y/Euoleate complex by Na3VO 4solution, were subjected to hydrothermal treatment at 200 °C for 6 h to initiate crystal growth. The resultant nanoparticles (average grain size 16.1 nm) show well-defined red luminescence due to radiative transitions from the 5D0 to 7FJ (J: 1-4) levels of Eu3+. Significantly, the nanoparticles disperse well in both water and nonpolar solvents, presumably due to an oleate double layer that self-organizes on the nanocrystalline surface. The effects of hydrothermal treatment on the crystal, luminescent, and morphological properties of amphipathic nanoparticles as well as the mechanism of their formation are discussed.