We study the effect of grain size on the dc field dependence of dielectric characteristics in BaSrTiO ceramics prepared by a sol-gel method. The samples were observed and analysed by SEM and X-ray diffraction. The dielectric constant samples decreases as the applied dc field increases. The influence of the dc field on the loss factor is much less than that on the dielectric constant. With increasing of the applied voltage, the T was increased and the peaks were suppressed and broadened. As the grain size increases, The maximum dielectric constant and the percentage change of dielectric constant under a dc field increase. A transition broadening and shift of T are observed as grain size decreases. © 2002 Elsevier Science B.V. All rights reserved.