Transparent SiC composites to microwave were fabricated using cold pressing method followed by sintering process at 1200 °C in air environment. However, zinc oxide and silicon were utilized as fillers. The X-ray diffraction and surface morphology revealed a crystal microstructure changes throughout the different mixing ratios of the composites associated with some pores due to sintering process, whereas SiO2 was detected in all XRD patterns duo to the oxidation of the Si. The dielectric properties and scattering characteristics of all composites in x-band were elucidated. The results showed low dielectric properties ~ < 5 in composites 70/20/10, 80/5/15, 80/10/10, 90/7.5/2.5, and 90/15/5 due to the increased oxidation in the composite that assist of charge mobility to passing through the thickness. On the other hand, all composites exhibited reflection loss higher than � 10 dB. This reduction accompanying increase of the transmission coefficient to be nearly 60 in which place the composite to be a promising candidate to microwave range. © 2023, The Author(s) under exclusive licence to Australian Ceramic Society.