This study presents a high-entropy tungsten bronze-type relaxor ferroelectric ceramic, $(\mathrm{Sr}_{0.5} \mathrm{Ba}_{0.5}) \mathrm{Pb}_{0.2} \mathrm{Na}_{0.2} \mathrm{Nb}_{2} \mathrm{O}_{6}$ (SBPLNN), designed through an equimolar-ratio element approach. The ceramic exhibits a giant recoverable energy density of 11.0 J·cm⁻³ and a high efficiency of 81.9%. Atomic-scale microstructural analysis reveals increased compositional heterogeneity and lattice distortion, which modulate the relaxor features and reduce polarization hysteresis, enhancing breakdown endurance. The study demonstrates that high-entropy design is an effective strategy for achieving ultrahigh energy storage characteristics in dielectric materials, with potential applications in advanced energy storage systems.This study presents a high-entropy tungsten bronze-type relaxor ferroelectric ceramic, $(\mathrm{Sr}_{0.5} \mathrm{Ba}_{0.5}) \mathrm{Pb}_{0.2} \mathrm{Na}_{0.2} \mathrm{Nb}_{2} \mathrm{O}_{6}$ (SBPLNN), designed through an equimolar-ratio element approach. The ceramic exhibits a giant recoverable energy density of 11.0 J·cm⁻³ and a high efficiency of 81.9%. Atomic-scale microstructural analysis reveals increased compositional heterogeneity and lattice distortion, which modulate the relaxor features and reduce polarization hysteresis, enhancing breakdown endurance. The study demonstrates that high-entropy design is an effective strategy for achieving ultrahigh energy storage characteristics in dielectric materials, with potential applications in advanced energy storage systems.