\Studies on preparation and characterization of Zn substituted Li-Mg ferrites having the general formula LixMg0.4Zn0.6-2xFe2+xO4 (where x = 0, 0.05, 0.1, 0.15, 0.2, 0.25, and 0.3) have been carried out. These polycrystalline ferrites were prepared by a standard ceramic technique. The single-phase. formation was confirmed from X-ray diffractograms. The lattice parameter 'a', bond lengths R-A, R-B and site radii r(A), r(B) were found to increase linearly with increase in Zn content. IR absorption spectral studies show two fundamental absorption bands v(1) and v(2) in the frequency range 600-400 cm(-1). The center frequency of v(1) and v(2) was found to shift towards low frequency side. The average grain diameter determined from SEM studies was found to increase with Zn content, it is maximum for Zn = 0.3 and then it decreases with further increase in Zn content. The Curie temperature was found to decrease linearly with Zn content. (C) 2002 Published by Elsevier Science Ltd.