BiFe O3 and PbTi O3 were introduced to a Sc-modified Pb (Fe23 W13) O3 compound with strong cation order to improve the multiferroic properties. It is found that the degree of cation order decreases as the amount of BiFe O3 or PbTi O3 increases. As a result, the saturation magnetization deteriorates. Solid solutions with BiFe O3 show an increase in both ferroelectric and magnetic transition temperatures. However, the ferroelectric remanent polarization is dramatically suppressed. In contrast, solid solution with PbTi O3 leads to an increase in the ferroelectric transition temperature, a decrease in the magnetic transition temperature, and a significant enhancement of remanent polarization. The composition 0.93 [0.79Pb (Fe23 W13) O3 -0.21Pb (Sc23 W13) O3] -0.07PbTi O3 shows the optimized properties of Tmax of 208 K, Pr of 3.6 μC cm2 between 120 and 210 K, TN of 209 K, and Ms of 0.23 μB f.u. (3.7 emug) at 10 K under 5 T. © 2007 American Institute of Physics.