The ethylene diamine (EDA)/salt solvent systems can dissolve cellulose without any pretreatment and/or derivatization. A comparison of the electric conductivity of different salts in EDA was made at 25°C, with conductivity decreasing in the order of KSCN>KI>NaSCN at the same molar concentration. Among the salts tested, potassium thiocyanate (KSCN) was capable of dissolving both high molecular weight (DP>1000) and low molecular weight (DP=210) cellulose, which was confirmed by polarized optical microscopy. 39K and 14N NMR experiments were conducted at 70°C as a function of cellobiose concentration with EDA/KSCN as the solvent. The results showed that cation (K+) of KSCN interacted with hydroxyl groups of cellobiose, whereas anion (SCN-) did not participate in dissolution. Regenerated cellulose was studied by infrared spectroscopy (FTIR) and wide angle X-ray diffraction (WAXD). Changes in the FTIR absorption bands at 1430 and 1317 cm-1 were associated with the change of the conformation of CH2OH at C-6. The changes in positions and/or intensities of absorption bands at 2900, 1163, and 897cm-1 were also related to the breaking of hydrogen bonds in cellulose. X-ray diffraction studies revealed that cellulose regenerated by coagulating cellulose solutions with water underwent polymorphic transformation from cellulose I to cellulose II.