Conditions of synthesis, such as concentration, temperature and pH, determine physico-chemical properties of nanoparticles. Mechanochemical method is an alternative approach to synthesize nanopartides in shorter time and using lower amount of solvent. Milling is an underestimated mechanochemical process that has been rediscovered by researchers chiefly as an economical and fast process. This paper presents the synthesis and the characterization of iron and cobalt magnetic oxides based on the mechanochemical preparation by milling the metal salt precursors in the presence of sodium borohydride. Moreover, the advantages in relation to the ordinary methodologies are presented and discussed. Characterization of the synthesized magnetic iron and cobalt particles showed amorphous products of average particle size in the range of 30-150 nm. The nanoparticle structures were obtained and confirmed by TEM, SEM and XRD analyses. N-2 adsorption-desorption isotherm showed narrow distribution of the nanopores in the range of 4 nm, which indicates a promising material for application as solid catalysts and feedstock for the fine chemistry industry.