Well-crystallized Cd-substituted Mn1-xCdxFe2O4 nanoparticles with x having values 0.0, 0.1 and 0.3 have been synthesized by hydrothermal route at 180oCwith the help ofNaOHasmineralizer. The as-prepared ferrite samples were characterized byXRD, SEMand vibrating samplemagnetometer (VSM). The XRD analysis showed that pure single phases of cubic ferrites were obtained with x up to 0.3. However, samples with x>0.3 form sodium cadmiumoxide (Na2CdO2) beside ferrite phase. The increase in the Cd-substitution up to x=0.3 increased the lattice parameter and the average crystallite size of the prepared ferrites. The saturation magnetization (Ms) increases with increase in Cd-substitution.