Two kinds of ionic liquids，1-（2-hydroxylethyl）-3-methyl imidazolium chloride（［HeMIM］Cl）and 1-allyl-3-methyl imidazolium chloride（［AMIM］Cl）were synthesized，and the chemical structures of the ionic liquids were confirmed by FT-IR and NMR spectrum.The solubilities of the ionic liquids for fir powder activated with different concentrations of NaOH were studied respectively.The chemical structure and crystalline form of fir powder before and after dissolution were analysed by FT-IR and XRD.It showed that the ionic liquids all had a good solubility for cellulose in activated fir powder，and the solubility of ［HeMIM］Cl was better than that of ［AMIM］Cl.When the concentration of NaOH to activate fir powder was 25％，the solubility was the best，and the crystallinity of the regenerated cellulose after dissolution decreased.