Abstract: In order to explore the demand pattern of potassium fertilizer for flue-cured tobacco variety Zhongchuan208, an experiment was conducted with Yunyan87 as the control, to investigate the absorption and utilization efficiency, accumulation and distribution characteristics, and the kinetic characteristics of potassium ion absorption of the two research materials. Results showed that the potassium absorption efficiency and utilization rate exhibited significantly higher in Zhongchuan208 than in Yunyan87. In the 28-84 days after transplanting, the potassium accumulation performed significantly higher in Zhongchuan208 than in Yunyan87, with an increase of 21.37%-111.76%. The potassium distribution rates in the two varieties followed the order of leaf>stem>root. In the 28-70 days after transplanting, the potassium accumulation performed significantly higher in Zhongchuan208 than in Yunyin87, with an increase of 80.53%-546.63%. Absorption kinetics showed that compared with Yunyan87, Zhongchuan208 behaved a stronger affinity and absorption capacity, and higher absorption rate for potassium ions, also a stronger tolerance to low potassium. In summary, the high affinity absorption capacity and absorption rate of Zhongchuan208 for potassium ions, led to a higher rate and level of potassium accumulation, thereby improving its absorption and utilization efficiency for potassium. The critical period for potassium absorption appeared from rosette to budding stage.