Nanocrystalline Li0.5-xAgxFe2.5O4; 0 ≤ x ≤ 1 samples were prepared using the citrate autocombustion technique. X-ray diffraction results indicate a single-phase spinel structure. The saturation and remanent magnetization of the samples have been determined as a function of the crystallite size. The Curie temperature improves 1.1 times on the undoped sample. While the saturation magnetization reaches a maximum value of 69 emu/gm. mole higher than the undoped sample at 50 emu/gm. mole. The activation energy at x = 0.075 is improved 17 times on the undoped sample. This concentration can be used for phase shifter, circulators, and microwave component applications.