The dielectric properties of (Ba0.6Sr0.4)TiO3 and Al2O3-doped (Ba0.6Sr0.4)TiO3 have been characterized. The grain size of the specimen is maximum for (Ba0.6Sr0.4)TiO3 that has been doped with 1 wt% Al2O3. The density and the real part of the relative dielectric constant each decrease as the Al2O3 content increases. The loss factor is minimum for (Ba0.6Sr0.4)TiO3 that has been doped with 2 wt% Al2O3. The dielectric constant of the specimens decreases as the applied de field increases. The influence of the de field on the loss factor is much less than that on the dielectric constant. The tunability is similar to 24% for (Ba0.6Sr0.4)TiO3 that has been doped with 1 wt% Al2O3.