An AB O3 perovskite multiferroic, where the B -site cation is responsible for the magnetic properties and the A -site cation with lone pair electron is responsible for the ferroelectric properties, was synthesized with the composition (La0.5 Bi0.5)(Mn0.5 Fe0.5) O3.09 at normal conditions. This oxide exhibits a ferromagnetic transition around 240 K with a well defined hysteresis loop, and a significant reversible remnant polarization below 67 K similar to ferroelectric behavior. The magnetic interaction is interpreted by the ferromagnetic Fe3+ -O- Mn3+ and antiferromagnetic Fe3+ (Mn3+) -O- Fe3+ (Mn3+) interactions competed with each other, whereas the ferroelectricity is predominantly due to the polar nature introduced by the 6 s2 lone pair of Bi3+ cations. © 2008 American Institute of Physics.