A convenient approach for the preparation of cellulose - carbon nanotubes (CNT) hybrid materials owning electromagnetic shielding properties, based on viscose (V) and TEMPO-oxidized viscose fibers (VO) is proposed. Viscose - carbon nanotubes (V-CNT) and TEMPO-oxidized viscose - carbon nanotubes (VO-CNT) composites were prepared by embedding carbon nanotubes on the surface of two types of cellulose fibers, that is, viscose and its C-6-oxidized derivative. The chemical composition, morphology, and thermal stability of the prepared hybrid materials were thoroughly investigated by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and thermogravimetric analyses. Moreover, electrical properties of the original and composite fibers were assessed. POLYM. ENG. SCI., 59:1499-1506 2019. (c) 2019 Society of Plastics Engineers