A novel method has been established for successive preparation of nano inorganic compound sols by pulsed laser ablation at the interface of solid and flow-liquid, and nano europium oxide-ethanol sol (NEO-ES) is obtained by this method firstly. The sol has been characterized by TEM, FT-IR, UV-VIS, fluorescence spectrum and XRD. The TEM result shows that europium oxide particles in NEO-ES have better dispersivity and their sizes are mostly below 5 nm. It is found that the vibration of ethanol molecule groups in the sol is obviously effected by nano europium oxide. The UV-VIS result shows that there are two strong absorption peaks at 244 nm and 284 nm vested in the characteristic peaks of Eu2+ and its emission fluorescence spectrum is a broad peak with maximum value at 408 nm of Eu2+. It is indicated that the Eu3+ of Eu2O3 is reduced to Eu2+ in the preparation course of the sol. The XRD shows that the nano europium oxide is mostly in non-crystalline form. The above results display that the characteristic of NEO-ES are closely concerned with the features of the method.