Abstract: To promote the quality of filamentous stems and to broaden their applications, a low-temperature pretreatment process suitable for filamentous stems was designed. The influences of the low-temperature pretreatment process on the appearance, morphology, physical indexes, chemical composition and production efficiency of tobacco stems were analyzed and compared with a "two-step moistening + two-step storing" process. The results showed that: 1) The low-temperature pretreatment process took normal temperature water as the stem moistening medium to raise the moisture content in tobacco stems up to about 48%, and then the stems were flattened and dried to obtain stem laminae. 2) The low-temperature pretreatment process reduced tobacco stem processing duration from 10 h to 6 h. 3) The mean thickness and standard deviation of stem laminae prepared by the low-temperature pretreatment process were 1.52 mm and 0.26 mm respectively. 4) Comparing with "two-step moistening+two-step storing" process, the epidermal tissue of the stem laminae prepared by the low-temperature pretreatment process had a higher degree of extrusion and stacking with more disordered fracture of ducts. As a result, the percentage of usable cut stems prepared by the low-temperature pretreatment process increased by about 10 percentage points. 5) Comparing with the "two-step moistening + two-step storing" process, the total amount of Amadori compounds in the treated stem laminae and cut stems was higher by more than 5%, which indicated that the low-temperature pretreatment process could promote the Maillard reaction in tobacco stems.