This study was conducted to elucidate the uses of chitosan extracted from Penaeus monodon. Chitosan is a natural polysaccharide that shapes structural additives inside the exoskeleton of crustaceans. In this research, chitin and chitosan had been extracted from the Penaeus monodon exoskeleton via the chemical system through a series of steps which include demineralization, deproteinization, and deacetylation. The chitosan received by the deacetylation system turned into analyzed for biochemical parameters like protein, lipid, carbohydrate, ash, moisture, degree of deacetylation, water binding capacity (WBC), fats binding capacity (FBC), and solubility. The statistics show that chitin contains 3.82% protein, 1.24% lipid, 68.45% carbohydrate, 2.9% ash, 9.6% moisture content, 67.60% DD, 640% WBC, 420% FBC, and 99% solubility which were higher than chitosan. The textile effluent was treated with extracted chitosan and chitosan membrane for 30 days. Maximum decolourization (55.56 to 95.75%) of the effluent occurs with 2 g of chitosan. This study concluded that chitosan is a promising absorbent for removing colour from textile effluent.