Cellulose is a natural polymer that is very abundant and widely used as raw materials for various industrial applications such as fiber, paper, membranes, paints etc. Modification of cellulose with succinic anhydride is one way to add value to the product. The purpose of this study is to synthesize cellulose succiniate derived from cellulose using ionic liquid [BMIM]Cl as solvent by MAOS method and to determine the factors that affect the degree of substitution (DS) of cellulose succinate produced. Cellulose was dissolved in [BMIM]Cl with various proportions and then reacted with succinic anhydride in the ratio of cellulose: succinic anhydride = 1:10 using a microwave reactor at various reaction conditions (time, temperature, microwave irradiation power). The FTIR spectrum of the product showed that cellulose succinate has been successfully synthesized which was characterized by the presence of a new peak at wave number of 1722,43-1726,29 cm-1 corresponded to the absorption band for C=O ester with a degree of substitution in the range of 0.66 to 1.33. The dissolution conditions and the reaction conditions influenced the degree of substitution of cellulose succinate produced. The more of [BMIM] Cl was used, the higher the degree of substitution of cellulose succinate produced.