Abstract: The first phase of the process was carried out in two phases, the first process was to prepare material from nano-crystalline structure of ZnFe₂O₄ and CdFe₂O₄ depending on formula of Cd_xZn_1-x Fe₂O₄ combination by ratio (x = 0.9) and mixing the compound of ZnFe₂O₄ with CdFe₂O₄ and they were prepared by using co-precipitation method because they give a great homogeneity to the powder particles. The second process used to blend the fractions by ratios (x) to the compound Cd_0.9Zn_0.1Fe₂O₄ with neoprene (Chloroprene Rubber, CR) by adding 3, 6 g. The XRD and Scanning Electron Microscopy (SEM) were investigated the structural properties for prepared samples and to determine length of unit cell, the results showed that ferrites had a cubic spinel structure and when increasing concentration (x) for the compound Cd_xZn_1-x Fe₂O₄ led to an increase the crystalline size and the distance between the crystalline surfaces, the ionic radius of the cadmium is greater than the ionic diameter of the zinc (0.83 A°). FESEM showed the increasing size of nanoparticles with increased concentration of Cadmium Ferrite (CdFe₂O₄) in relation to compound Cd_xZn_1-x Fe₂O₄, the elements of the ferrite structures showed by (EDS) and mixed compound of ferrite with the neoprene (Chloroprene Rubber, CR) according to the weight ratios 3, 6 g. VNA was investigated within the X-band of the microwave 8-12 GHz, the best result was obtained by adding 6 g of neoprene (Chloroprene Rubber, CR) for attenuation microwaves. The real part of the dielectric constant and the imaginary part of the dielectric constant were calculated as a frequency function at the X beam within the microwave region. The real part of amplitude refers to the amount of energy from the external electric field stored in the material, the imaginary part refers to the scattered energy or loss of energy.