YVO4: Eu3+ nanoparticles were fabricated by pulsed laser ablation in water-ethanol mixtures with ethanol volume fractions of 0%, 10%, 30%, 50%, and 100%. Scanning electron microscopy and transmission electron microscopy were performed to characterize the nanoparticle morphologies and crystallinities. Photoluminescence and UV-vis absorption were used to investigate the optical properties. The results showed that only ovoid-like nanoparticles were obtained when using deionized water as the liquid medium. Sphere-shaped and ovoid-shaped nanoparticles simultaneously appeared after adding ethanol to the liquid; and finally, only spherical nanoparticles were obtained in pure ethanol. The crystallinities and PL intensities of the nanoparticles varied inversely to the corresponding liquid viscosity. When increasing the ethanol content, the UV-vis showed a blue shift that could be ascribed to the decreased covalence of V O bonds. (C) 2017 Elsevier B.V. All rights reserved.