The BaSrZrTi O (BSZT) thin films were deposited via sol-gel process on LaNiO-coated silicon substrates. The grain size decreased and the microstructure became dense when substitute Zr for Ti. Dielectric properties were investigated as a function of temperature, frequency and direct current electric field. The temperature dependent dielectric measurements revealed that the thin films have diffuse phase transition characteristics. The tunability of BaSrSnTi O thin films is about 57%, at an applied field of 415kV/cm and measurement frequency of 1MHz. It was observed that the leakage current density of BaSrZrTi O is higher than that of BZT thin films. © 2004 Elsevier Ltd. and Techna Group S.r.l. All rights reserved.