Microwave dielectric properties have been investigated on the solid solution series (BaxSr1-x)(Zn1/3Ta2/3)O3 with x = 0, 0.3, 0.5, 0.7, 1.0. The variation in dielectric constant (ε) and temperature coefficient of resonant frequency (τf) with respect to x are not monotonous. An anomaly exists for the composition Ba0.5Sr0.5(Zn1/3Ta2/3)O3. The Q × f product decreases with increase in the Sr concentration. The dielectric properties of these compounds are related to the structural distortion due to octahedra tilting.