A deeper understanding of the effect of Pr substitution on crystal structure and magnetic properties of bismuth ferrite was provided by performing solid-state synthesis, X-ray diffraction, and magnetization measurements of the Bi 1-xPr xFeO 3 compounds. Polycrystalline samples were prepared by a conventional solid-state reaction method using the high-purity oxides Bi 2O 3, Pr 6O 11. The results show that the spectral contribution from the substitution induced phase increases with growing Pr content to completely suppress contribution from the rhombohedral phase for the compounds with x≥0.16. Comparing the established concentration ranges with those reported for La, Nd, and Sm doped series imply that decreasing ionic radius of a substituting lanthanide shift the phase boundaries toward smaller x to narrow stability ranges of the parent rhombohedral and intermediate orthorhombic Pnam.