The CoFe2O4, NiFe2O4 and ferrites ZnFe2O4were prepared by auto-combustion method. The scanning electron microscopy (SEM) was used for investigation the microstructural features of combustion reaction products. The structural evolution at different process stages of spinel ferrites are investigated by powder X-Ray diffraction (XRD) and Fourier transform infrared techniques (FT-IR). The XRD patterns of obtained products after calcination confirm the single-phase cubic spinel type. The average crystallite sizes for different compounds were found to be in nanometer range. The FT-IR studies show two fundamental absorption bands which are assigned to the vibration of tetrahedral and octahedral complexes of the structure of spinel. Powder specific surface area was measured using the multi point Brunauer-Emmet-Teller method (BET). BET results shows, that after calcination sub-micrometer sized primary particles have been agglomered into larger secondary particles. Atomic force microscopy (AFM) was used to study calcined ferrite particle dimensions. AFM images shows that particles are in nanometer dimensions. Room temperature D.C. electrical conductivity measurements of the spinel ferrites show that obtained compounds lover coductivity compared to spinel ferrites obtained with convenctional ceramic technique.