This study aims to investigate the effect of carbon fibers (CFs), recycled polypropylene (PP) selvages, and glass fibers (GFs) on the electromagnetic shielding effectiveness and mechanical properties of composite polyester (PET)‐wrapped yarns and composite PET woven fabrics. The PET/PP‐, PET/PP/CF‐, and PET/PP/GF‐wrapped yarns are manufactured via a rotor twister with various rotary rate. A looming machine is used to fabricate the mentioned wrapped yarns into woven fabrics, and thus the electromagnetic shielding effectiveness and mechanical properties are examined. The results show that various rotary rates influence the diameter and wrapped angle of the wrapped yarns, as well as their tensile strength and elongation. Woven fabrics that are composed of the wrapped yarns with a small diameter have a dense fabric structure, which in turn results in a decrease in air permeability and an increase in tensile strength. The woven fabrics are composed of PET yarns and CFs, in an attempt to be used in industrial or everyday protective clothes that secure the safety and standard of living. POLYM. COMPOS., 40:E1910–E1917, 2019. © 2018 Society of Plastics Engineers