The polycrystalline samples of Fe3-xMnxO4 (0.10 <= x <= 0.50) were prepared by a solid-state route reaction method. X-ray diffraction pattern shows that Mn2+ doped magnetites are in single phase and possess cubic inverse spinel structure. The resistivity measurements (10 < T < 300 K) for x = 0.0 and 0.01 confirms the first order phase transition at the Verwey transition T-V = 123 K and 117K, respectively. No first order phase transition was evidenced for Fe3-xMnxO4 (0.10 <= x <= 0.50). Small polaron model has been used to fit the semiconducting resistivity behavior and the activation energy epsilon(a), for samples x=0.10 and 0.50 is about 72.41 meV and 77.39 meV, respectively. The Raman spectra of Fe3-xMnxO4 at room temperature reveal five phonons modes for Fe3-xMnxO4 (0.01 <= x <= 0.50) as expected for the magnetite (Fe3O4). Increased Mn2+ doping at Fe site leads to a gradual changes in phonon modes. The Raman active mode for Fe3-xMnxO4 (x=0.50) at congruent to 641.5 cm(-1) is shifted as compared to parent Fe3O4 at :congruent to 669.7 cm(-1), inferring that Mn+2 ions are located mostly on the octahedral sites. The laser power is fixed to 5 mW causes the bands to broaden and to undergo a small shift to lower wave numbers as well as increase in the full width half maxima for A(1g) phonon mode with the enhancement of Mn2+ doping. Mossbauer spectroscopy probes the site preference of the substitutions and their effect on the hyperfine magnetic fields confirms that Mn+2 ions are located mostly on the octahedral sites of the Fe3-xMnxO4 spinel structure. (c) 2011 Elsevier B.V. All rights reserved.