The effect of substitution of Sr at the A site of Ba(Zn 1/3Ta2/3)O3 was investigated with respect to tolerance factor (t ) which determines the degree of packing of A and B site ions of perovskite unit cell, with an intension to understand the correlation between the temperature dependent dielectric properties with structure. The investigation reveals that the Ba rich compositions with highly symmetric cubic phase exhibits negative variation of dielectric constant with temperature and the Sr rich compositions with distorted structure always show positive variation of dielectric constant with temperature. The profile of τε variation of all the compositions was scaled with respect of reduced temperature which exhibits an exact signature of τε variation with the compositions at room temperature. The observed mechanism was explained using Clausius Mossoti equation. © 2011 The Japan Society of Applied Physics.