Lanthanum-doped bismuth ferrite (Bi 1-x La x FeO 3 , wherein x is equal to 0, 0.15, 0.3, and 0.4) crystallites were synthesized by hydrothermal method. In the synthesis, precursor composition, potassium hydroxide concentration, and hydrothermal temperature and time played important roles in the crystallinity and morphology of Bi 1-x La x FeO 3 crystallites. Pure Bi 1-x La x FeO 3 crystallites could be obtained when x \ 0.3, and ferroelectric transition temperature decreased from 834.2 to 828.7°C with increasing La doping. The growth mechanism of the Bi 1-x La x FeO 3 crystallines was also discussed. Furthermore, our results showed that La doping greatly enhanced the remnant polarizations.