In this work nanocellulose substrates e. g. cellulose nanofibrils and nanocrystals were isolated from an abundant renewable resource Ampelodesmos mauritanicus fibers. Cellulose nanocrystals CNCs were isolated from the fibers by means of acid hydrolysis while cellulose nanofibrils (CNFs) were isolated by combination of TEMPO-mediated oxidation and mechanical shearing using high-pressure homogenizer. The chemical composition of Ampelodesmos mauritanicus fibers was analyzed prior to the isolation of the different nanocellulose substrates in order to optimize their extraction processes. The morphology, geometry, and distribution of the cellulosic nanoparticles were performed using scanning electron microscopy (SEM) and transmission electron microscopy (TEM), and the crystalline structure and the crystallite size were evaluated by X-ray diffraction (XRD). The surface charge of CNCs and the degree of oxidation of CNFs were examined by Zeta potential and conductometric titration. The nanocellulose substrates extracted from Ampelodesmos mauritanicus fibers exhibit a diameter of 5.64 ± 1.5 nm and length of 108.95 ± 13.7 nm for CNCs and 6.1 ± 1.5 nm and a few micrometers for CNFs.