In the present study, a facile one-pot production of nanocellulose from ripe and unripe Saba’ banana (Musa acuminata x balbisiana) peel was conducted by utilising hydrogen peroxide (H2O2) as an oxidising agent prior to hydrolysis with sulphuric acid (H2SO4) at different concentrations (8%, 24% and 40%). Proximate and chemical compositions of the ripe and unripe banana peel (BP) powder were analysed, followed by physicochemical characterisations of the resulting nanocellulose by using Scanning Electron Microscopy (SEM), Fourier Transform Infrared (FTIR) spectroscopy and Dynamic Light Scattering (DLS). FTIR analysis has confirmed the successful removal of non-cellulosic components from the BP through the distinguishable spectra of both the ripe and unripe BP powder with the H2O2/H2SO4- treated samples. SEM analysis revealed morphological changes of the BP powder from an irregular structure with the presence of starch granules to lamellar and fibrous structures after the H2O2/H2SO4 treatment and freeze-drying. The size of the nanocellulose is strongly influenced by the concentration of H2SO4 used. Nanocellulose from ripe BP produced by using the 40% H2SO4 has the smallest size with D50 < 80 nm. These findings suggest the potential of banana peel, an abundant agricultural waste to be valorised into value-added materials with significant economic potentials.