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• Five kinds of pyrochlore high-entropy rare-earth zirconates have been prepared. • High-entropy strategy improves the electrical conductivity of rare-earth zirconate. • (Nd 0.2 Eu 0.2 Sm 0.2 Gd 0.2 Dy 0.2) 2 Zr 2 O 7 has a conductivity of 7.1 × 10–3 S·cm–1 at 1073 K. • Higher mobile vacancy concentrations, lower activation energy and the preferential O-ion migration pathway result the enhanced ion conductivity. In the present work, a series of new high-entropy rare-earth zirconates were prepared by a solid state reaction method. The crystal structure, microstructure and electrical properties of high-entropy rare-earth zirconates were characterized by means of X-ray diffraction, Raman spectroscopy, scanning electron microscopy, transmission electron microscopy and electrochemical impedance spectroscopy. All the high-entropy rare-earth zirconates have a single-phase pyrochlore structure with a relative density of more than 95.7%. The grain sizes of high-entropy rare-earth zirconates are 1.3–2.4 µm, which are finer than low-entropy rare-earth zirconates prepared by the same process. (Nd 0.2 Sm 0.2 Eu 0.2 Gd 0.2 Dy 0.2) 2 Zr 2 O 7 has the excellent electrical conductivity of 7.1 × 10–3 S·cm–1 at 1073 K. [ABSTRACT FROM AUTHOR]