High-amylose maize starch (HAS) was used to produce a fibrous 3D network nanosystem aiming at providing an efficient and stable emulsion stabilizer characterized by being robust against storage, freeze-thawing, high temperatures and mechanical shearing. This approach is principally different from the usually applied stabili-zation systems based on surfactants or small solid particles. Here, we utilized a sodium hydroxide-based low -temperature, chemical gelatinization protocol to minimize molecular degradation, and ethanol nanoprecipitation to reassociate the polysaccharides nanoparticles (NPs) to form a 3D nanosystem. Octenyl succinic anhydride (OSA) substitution was used for modulation of the amphipathic properties of the nanosystem to enhance the emulsfying capacity. With increased OSA substitution, light transmittance of the NPs solutions increased and the size distribution of the NPs decreased down to 100 nm. The obtained emulsions were characterized by being water in oil (W/O) systems, and the NPs were distributed in the oil phase. OSA substitution and NPs concen-tration contributed combinedly to the emulsification capacity. The nanosystem, at 5% concentration with 20% OSA modification, had droplets of approximately 1 mu m in diameter, and could withstand a 60-day-long storage, five-cycle freeze-thaw and thermal stability tests. In addition, it also displayed higher mechanical stabilities to shear-thinning.