Transition metal substituted Zinc oxide (ZnO) has drawn a great deal of attention due to its excellent properties. Zn0.9Mn0.05Fe0.05O sample synthesized was by Sol-gel wet chemical precipitation route at temperature 350 degrees C. The crystallinity and the structure of Zn0.9Mn0.05Fe0.05O was determined by X-ray diffraction by Cu-Ka radiations operated at 40kV and 35mA in the range of 20 degrees to 80 degrees. The pattern gets indexed in wurtzite (hexagonal) structure with lattice constants a=b=3.2525 angstrom and c=5.2071 angstrom and approves the single phase material with no impurity. The values of particle size assessed by Debye Scherer's (DS) formula lie in the range of 13nm to 33nm indicating the nano-crystalline nature of the sample. The morphological analysis of the sample was performed by Scanning electron microscopy (SEM) and Transmission electron microscopy (TEM) measurements. The observed size of Zn0.9Mn0.05Fe0.05O nanoparticles by TEM micrograph exhibits the similar trend with the size calculated by Debye-Scherer formula. TEM image show the irregular shape of the nanoparticles and particle size lies in the range of 10-35nm. Similar to SEM image, the slight agglomeration of the nanoparticles have been observed from TEM.