In this research the additive effect of Zirconium Oxide (ZrO2), Copper oxide (CuO) nanoparticles to epoxy resin as a matrix have been studied, in addition to manufacturing hybrid composites from the same nanoparticles which are (CuO/ZrO2) to epoxy resin as a matrix too. The hand lay-up method is using to manufacturing the composites from the epoxy resin and the nanoparticles with different weight ratios ((0, 0.3, 0.6, 0.9) wt%), the thermal and dielectric tests have been done of all prepared composites. The effect of the weight ratio of the reinforcement materials on the thermal properties of all-polymer composites has been studied also. The practical results have shown that the differential scanning calorimetric (DSC) test has shown that the glass transition temperature of all-polymer composites increases at all weight ratios of reinforcement materials compared with pure epoxy and the highest value of glass transition temperature is to the composite (EP-ZrO2) which equal (89.97 °C), also the crystalline melting temperature of all-polymer composites has shown irregular behavior compared with pure epoxy by increasing the weight ratio of reinforcement materials. The effect of the weight ratio of the reinforcement materials on the dielectric properties of all-polymer composites have been studied, the practical results have shown a decrease in dielectric constant with increase the frequency for all weight ratios of reinforcement materials, and also increasing the dielectric constant with increasing the weight ratio of the reinforcement materials at the same frequency.