Water soluble esterified nanocellulose (ENC) was prepared with various anhydrides in expeditious, yet ecofriendly ways by using deep eutectic solvent (DES), ultrasonic and microwave irradiation. Phthalic anhydride and DES made of oxalic acid and choline chloride were mainly used as a reagent and solvent. Results indicated that shape and size of ENC could be varied by preparation methods. Analyses of ENC suggested that oxalic acid participated as both solvent and reactant, forming various types of anhydrides with reagent and cellulose. Characterization of ENC was performed by various instruments such as FTIR, TGA, X-ray diffraction, SEM, and zeta potential analyzer.