Nanocrystalline (20 nm) lead magnesium niobate (PMN) powders were prepared via a chemical process. This process involved the addition of aqueous niobium tartrate, lead-ethylenediaminetetraacetic acid, and magnesium-polyvinyl alcohol complex to produce a homogeneous solution. After the complete evaporation of the resulting homogeneous solution, the complexes decomposed and produced a black, fluffy precursor material. The precursor material on calcination up to 850 °C/2 h produced nanocrystalline PMN powders with the corresponding average particle size 20 nm. PMN powders modified with lead iron niobate (PFN) (1 – x)PMN–xPFN (x = 0.1, 0.2, and 1) were also prepared using this route and investigated through x-ray diffraction studies.