Spinel-type ferrites MFe 2 O 4 (M=Ni, Zn, Mn, Co, Mg) are among the most important magnetic materials and they are prepared mostly by solid-state reaction at elevated temperatures. We proposed in the past [V. Sepelak, I. Bergmann, A. Feldhoff, P. Heitjans, F. Krumeich, D. Mmenzel, F.J. Litterst, S.J. Campbell, K. Becker, J. Phys. Chem. C 111 (2007) 502612; S. Bid, P. Sahu, S.K. Pradhan, Physica E 39 (2007) 175] a mixed synthetic route that uses both mechanical and thermal energy. In the present work the strategy is applied to the preparation of NiFe 2 O 4 starting from mixtures of 2NiCO 3 ·3Ni(OH) 2 ·4H 2 O–FeC 2 O 4 ·2H 2 O subjected to both mechanical and thermal annealing. TG/DSC measurements allowed to obtain information on the reaction mechanism and also a ΔH for the reaction between the constituent oxides yielding NiFe 2 O 4 in good agreement with the deduced from the data of ΔG° versus T. The XRPD of the samples recovered after the TG/DSC runs shows the reflexions of NiFe 2 O 4 only when starting from milled mixture. NiFe 2 O 4 can be prepared by thermal treatment of physical mixtures 2NiCO 3 ·3Ni(OH) 2 ·4H2O–10FeC 2 O 4 ·2H 2 O by 36h at 1100°C. On the contrary 12h at 400°C yield XRPD-phase pure NiFe 2 O 4 . Samples of NiFe 2 O 4 obtained from the milled mixture show a surface area that decrease by increasing the synthesis temperature from 400°C to 700°C. On the basis of measurements of molar thermal capacity, it is demonstrated that NiFe 2 O 4 can be obtained by a 12h annealing at 450°C of the mechanically activated mixture.