Faraday effect measurements of holmium oxide (Ho 2 O 3 ) 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 Ho 2 O 3 ceramics was measured for temperatures 15-305 K at 1.064 µm wavelength. The Verdet constant dispersion for wavelengths 0.5-1 µm and 1.064 µm was measured for both nondoped Ho 2 O 3 ceramics and Ho 2 O 3 ceramics doped with terbium Tb 3+ (0.2 at. %) and cerium Ce 3+ (0.1 at. %) ions. The results suggest that the relatively low level of doping of Ho 2 O 3 with these ions has no significant boosting impact on the Faraday effect. Therefore, other compositions of Ho 2 O 3 ceramics-based magneto-optical materials, as well as various doping concentrations, should be further examined.