Praseodymium oxide (Pr6O11) as a rare-earth functional materials, has been widely applied to the catalyst, ceramic pigments, oxygen storage materials, high-conductivity materials in many areas. In this paper, we have study the relevant process parameters of the direct synthesis which make the nano-structure of praseodymium oxide. By controlling the reaction during the deposition process parameters, we can make the praseodymium oxide of good thermal stability.The experimental results show that: calcination temperature and calcination reaction time are the main factors that affect the nano-structure of praseodymium oxide。