Faraday effect measurements of holmium oxide (Ho₂O₃) ceramics-based magneto-optical materials, highly potential material candidates for high-energy laser Faraday isolators, are presented in this paper. Temperature dependence of the Verdet constant of nondoped Ho₂O₃ ceramics was measured for temperatures 15–305 K at $1.064~\unicode[STIX]{x03BC}\text{m}$ wavelength. The Verdet constant dispersion for wavelengths 0.5–$1~\unicode[STIX]{x03BC}\text{m}$ and $1.064~\unicode[STIX]{x03BC}\text{m}$ was measured for both nondoped Ho₂O₃ ceramics and Ho₂O₃ ceramics doped with terbium Tb³⁺ (0.2 at. %) and cerium Ce³⁺ (0.1 at. %) ions. The results suggest that the relatively low level of doping of Ho₂O₃ with these ions has no significant boosting impact on the Faraday effect. Therefore, other compositions of Ho₂O₃ ceramics-based magneto-optical materials, as well as various doping concentrations, should be further examined.