A facile and environmentally friendly synthesis method has been employed to prepare micron or submicron single-crystal Bi1–xLaxFeO3 with different particle shapes. Various forms of the crystallite are obtained, such as cubic, tetragonal, and semi-sphere crystallites, by means of molten salt synthesis. The thermal stability of BiFeO3 perovskite is greatly enhanced by substitution with LaFeO3. The pure phase ofBi1–xLaxFeO3 can be obtained without the use of the rapid thermal technique by introducing with small amounts of LaFeO3 into BiFeO3. The structure of Bi1–xLaxFeO3 changes from rhombohedral BiFeO3 (R3c) to orthorhombic LaFeO3 (Pnma) with an intermediate orthorhombic phase (C222), which is demonstrated by the X-ray diffraction, Raman spectoscopy, and electron diffraction. The formation of Bi1–xLaxFeO3 can be completed in a short time (i.e. 30 min), as the reaction temperature reaches the melting point of NaCl. For the synthesis of Bi0.4La0.6FeO3, the nuclei occur with an irregular tetragonal shape in the initial nucleation stage and then grow with a regular tetragonal profile in the following growth stage. The Bi1–xLaxFeO3 crystal growth was revealed to follow the Ostwald ripening mechanism.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)