In this study, chitosan was extracted from Penaeus monodonshrimp shell waste and was used as a bio-sorbent to remove Safranin O (SO) dye in aqueous solution. Batch adsorption experiments were carried out to evaluate the influence of solution pH, chitosan dosage, contact time and initial SO concentration on the adsorption process. The study was conducted varying contact time from 1 to 720 min, adsorbent dose from 0.1 to 3 g, adsorbate concentration from 10 to 200 mg.L-1, pH from 3 to 10. The results showed that adsorption of Safranin O by chitosan reached to equilibrium after 120 min and after that a little change of chromium removal efficiency was observed. The maximum adsorption capacity of Safranin O calculated by Langmuir model was 17.86mg.g-1was obtained at room temperature (25°C±2), pH of 7, chitosan dose 0.2 g and SO concentration of 50 mg.L-1. The kinetics of the adsorption process followed the pseudo-second-order kinetics model withthe correlation coefficients R2 of 0.95.The Langmuir and Freundlich isotherm adsorption models described well the Safranin O adsorption process, with R2 of higher than 0.95. The study demonstrated that the chitosan can be extracted fromPenaeus monodonshrimp shellssimply and can be effectively used to remove Safranin O cationic dye in aqueous solution.