Cytotrophoblast cell differentiation into syncytiotrophoblast cells is a complex and delicate process, and the mechanism needs a large number of further studies. Knockout of 14-3-3τ expression and some further investigations were performed in the syncytiotrophoblast cell formation with RNA interference (RNAi) technology. The study found that the 14-3-3τ expression level with the formation of syncytiotrophoblast cells increased. Hypoxia inhibited the formation of syncytiotrophoblast cells where 14-3-3τ expression level decreased. RNAi reduced 14-3-3τ expression, and reduced the formation of syncytiotrophoblast cells. So that 14-3-3τ is not only involved in the cell regulation, but also in the formation of syncytiotrophoblast cells. 14-3-3τ is an important regulatory factor which inhibits the formation of hypoxia.