Lanthanum-doped lead zirconate stannate titanate ceramics were successfully compacted to full density by spark plasma sintering (SPS). SPS samples densified at 900degrees or 950degreesC exhibit nearly full density and fine grain size (about 300 nm). Compared with samples from conventional sintering (CS), SPS samples show larger permittivity accompanied by a deterioration in dielectric loss and special strain hysteresis loops similar to those of ferroelectric relaxors, with a diffuse AFE-FE phase transition and less field-induced longitudinal strain. The differences in the properties of SPS and CS materials are attributed to the variations of the resultant microstructures, especially the grain size, of the ceramics.