© 2017 Taylor & Francis Group, LLC. The Ba 1- x Sr x (Fe 0.5 Ta 0.5 )O 3 ceramics were fabricated via a solid-state technique. Effects of Sr-doping on phase formation, densification and dielectric properties were investigated. XRD data revealed that all ceramics had perovskite structure with cubic symmetry. However, single phase was obtained only at x ≤ 0.1. All samples presented high dielectric constant-frequency dispersion with high dielectric constants. Complex impedance analysis indicated that heterogeneous conduction that occurred in the studied ceramics, should be the primary reason for the d ielectric constant-frequency dispersion with high dielectric constants. However, the electrode effect was found to dominate for the x = 0.1 ceramic as a result in the very strong dielectric constant-frequency dispersion with very high dielectric constants (ϵ r ∼ 1.58 × 10 5 at 310°C).