Featured with high polarization and large electric field‐induced phase transition, PbZrO3‐based antiferroelectric (AFE) materials are regarded as prospective candidates for energy‐storage applications. However, systematical studies on PbZrO3‐based materials are insufficient because of their complex chemical compositions and various phase structures. In this work, (Pb0.94La0.04)(Zr1‐x‐ySnxTiy)O3 (abbreviated as PLZST, 0 ≤ x ≤ 0.5, 0.01 ≤ y ≤ 0.1) AFE system was selected and the energy‐storage behavior was regulated. It is found that low Ti content benefits to obtain satisfactory electric breakdown strength, realizing high energy‐storage density. With Sn content increasing, the electric hysteresis decreases gradually, which is beneficial to improve energy conversion efficiency. As a result, a large recoverable energy‐storage density of 9.6 J/cm3 and a high energy conversion efficiency of 90.2% were achieved in (Pb0.94La0.04)(Zr0.49Sn0.5Ti0.01)O3 ceramic. This work reveals energy‐storage behavior of PLZST AFE materials systematically, providing reference for performance tailoring and new material designing in energy‐storage applications.