Long-chain fatty acid esters of cellulose were synthesized in cellulose LiCl/DMAc（lithium chloride/N

N-dimethylacetamide）homogenous solution system by using p-toluenesulfonyl chloride as co-reaction reagent，and in situ activation of the long-chain fatty acid. The structure and properties of long-chain fatty acid esters of cellulose were characterized by means of IR

1H NMR

XRD

TG

etc. The esterification conditions were investigated. The results showed that the long-chain fatty acid esters of cellulose with the highest degree of substitution（DS）could be prepared when the esterification was carried out at 85℃ for 24 h with the mole ratios of repeat units of cellulose（AGU）∶long-chain fatty acid (RCOOH)∶ p-toluenesulfonyl chloride (TosCl) =1∶3∶3

and the degree of esterification decreased with the growth of the number of carbon atoms of long-chain fatty acid. TG analysis revealed that esterification weakened the inter-molecular and intra-molecular forces of cellulose