Relaxer ferroelectrics are highly attractive in electrocaloric due to large breakdown electric field and wide phase transition temperatures, which has great potential applications in solid-state cooling. In this work, relaxer ferroelectrics are synthesized by a traditional solid state reaction method. Phase transition and relaxer characteristics are studied by temperature dependent dielectric spectrums. Temperature dependent ferroelectric properties are also studied to calculate electrocaloric effect. Maximum value of refrigeration efficiency η ( ΔT/ΔE ) is about 0.079 K·cm/kV, our result lays a foundation and provides a reference for studying high efficiency solid-state electrocaloric refrigeration. Pyroelectric energy harvesting are studied, maximum pyroelectric energy harvesting is 279 kJ/cm 3 .