Oil Palm Empty Fruit Bunches (OPEFB) and mesocarp can mainly be used as a raw material for nanocrystalline cellulose (NCC), which was previously converted into α-cellulose. Although this biomass is abundant, it needs to be observed that which part of the OPEFB and mesocarp are more suitable to be used as a raw material for NCC in terms of the characteristics of α-cellulose, especially the degree of crystallinity. To isolate α-cellulose, the lignocellulose material was dissolved into acid, delignified to remove lignin and bleached, then dissolved it with NaOH 17.5%. The samples were then analyzed for the composition of fiber chemicals, determined the yield of α-cellulose, degree of crystallinity (XRD), functional groups (FTIR) and surface morphology (SEM). From the observation, it is known... that OPEFB fibers have relatively higher cellulose levels the mesocarp fibers. From the visual appearance, α-cellulose color of OPEFB is whiter than the mesocarp. Comparatively, the yield of α-cellulose and the degree of crystallinity of fiber and α-cellulose OPEFB are higher than the mesocarp. The observation of functional groups showed that there was a difference between fiber and α-cellulose, but there was no difference between α-cellulose and OPEFB and mesocarp. The observation of the surface morphological structure of α-cellulose shows that the OPEFB has a more unified structure by forming regular microfibrils, while the mesocarp surface is irregular. Based on the analysis, it can be concluded that OPEFB fibers are more suitable to be used as raw material for nanocrystalline cellulose than mesocarp fibers.