Abstract: To control and improve blending uniformity during tobacco threshing and redrying processes, the changes in nicotine content's coefficient of variation (CV) in tobacco leaves during separating and processing were analyzed by comparing three control methods of consistent processing. The results showed that the CVs of nicotine content in redried tobacco strips of all batches under the blend proportion control method ranged from 3.78% to 7.63%, with the average CV of 5.47%. The CVs of nicotine content in redried strips of all batches under the mixing combination control method were from 2.45% to 3.90%, with the average 2.92% CV. Under the similarity combination control method (whereby cured tobacco leaves were grouped according to their specific planting areas, stalk positions, varieties and appearance quality to form so-called similarity units. These units were stored in order and combined into processing units, which could represent the quality of the whole batch), the CVs of nicotine content in redried strips were 3.01%-3.59%, with the average 3.24% CV. There was no significant difference on CVs of nicotine contents between the mixing combination and the similarity combination control methods, which were significantly lower than those of the blend proportion control method.