Cushuro (Nostoc sphaericum) is a blue-green edible freshwater microalgae of ancestral use as a traditional food in the Andean regions of Peru. Knowledge of the extraction process conditions and characteristics of cushuro biomass polysaccharides are instrumental to expand its range of applications and appraise its potential utilization as a hydrocolloid ingredient in food and other applications. Polysaccharides acid extract (PCAcE) and polysaccharides aqueous extract (PCAqE) with hot water at 90 °C were extracted from cushuro (Nostoc sphaericum) biomass collected from the Department of Ancash, Peru. PCAcE showed higher extraction yield (49.0 ± 0.5 %), purity (83.3 ± 0.3 %), emulsifying capacity (55.6 ± 1.0 %), foaming capacity (8.3 ± 0.3 %), water holding capacity (3.0 ± 0.11 g/g) and DPPH radical scavenging activity (73.0 %) than PCAqE. Also, FTIR spectra showed a typical polysacch...