Abstract: Cellulose hollow fiber membrane was spun with ionic liquid 1-allylic-3-methyl imidazole chloride (［AMIM］Cl) as solvent. The influence of the molecular weight and the mass fraction of polyethylene glycol(PEG) on the structure and properties of cellulose hollow fiber membrane were investigated. Field emission scanning electron microscopy (FESEM) was used to observe the membrane's inner and outer surface morphology structure. The pure water flux, porosity, maximum tensile strength and elongation of membrane at break were tested. The results showed, with the decrease of molecular weight of PEG, outer and inner surface structures of hollow fiber membrane become neater, membrane porosity and pure water flux increased, the maximum tensile strength and elongation at break of the membrane properties gradually become smaller. With the increasing of mass fraction of PEG, membrane porosity and pure water flux become larger, and the maximum tensile strength and elongation at break of the membrane criterion decrease gradually. When the molecular weight of PEG is 2.0×104 and mass fraction is 5%, there are the best permeability and mechanical performance.