Several adsorbents have been used to remove different dyes from wastewater. Chitosan is a type of biopolymer that is very good to remove many types of dyes from aqueous solution. This study has investigated the comparisons of adsorption capacity between Indigo and Scarlet dye leading to effectively remove hazardous dyes for water treatment. The equilibrium time of Indigo adsorption is 24 hours for 30oC and 35oC and 40oC, respectively. While, The equilibrium time of Scarlet adsorption is 12 hours for 30oC and 35oC and 40oC, respectively. In addition, the theories of Langmuir and Freundlich isotherms show different types of adsorption. For Scarlet, the Langmuir isotherm model shows a better fit than Freundlich isotherms at 35oC and 40oC. Whereas, Freundlich isotherm is better than Langmuir in case of 40oC. The maximum adsorption capacities of Indigo and Scarlet are 64.94 and 97.09 mg g-1, respectively. According to the result, it appears that chitosan can absorb Scarlet better than indigo. In addition, the kinetic data show that adsorption between chitosan and these two dyes follows the pseudo-second-order