In order to investigate the effects of rootzone potassium fertilizer on the yield and potassium uptake of fluecured tobacco in calcareous soil of Huanghuai tobacco region,the field experiment was conducted to study the effects of citrate acidsoluble potassium fertilizer and potash fertilizer on the yield,potassium concentration and potassium uptake of fluecured tobacco.A total of nine treatments were conducted for the tests,namely CK,CP1,CP2,WP1,WP2,CW150%,CW250%,CW175% and CW275%(CK indicates control,CP indicates that only citrate acidsoluble potassium fertilizer is applied,WP indicates that only potash fertilizer is applied,CW indicates that citrate acidsoluble potassium fertilizer in combination with potash fertilizer is applied,and figures 1 and 2 indicate that application rates are 225 kg/hm2 and 300 kg/hm2 respectively,percentage indicates the ratio of potash fertilizer applied).The results showed that the potassium content of tobacco leaves showed a downward trend with the growth period,and the potassium content of tobacco leaves in different fertilizer treatments was higher than that of CK.Under different fertilization treatments,the soil potassium transport distance in the vertical and horizontal directions was relatively small.Rootzone potassium fertilization directly and effectively increased the content of available potassium in the root zone of tobacco.Compared with 225 kg/hm2,the application of potassium(K2O)at the rate of 300 kg/hm2 significantly increased the potassium content of the leaf and potassium fertilizer utilization efficiency(P<005).The content of potassium,the content of soil available potassium and the utilization rate of potassium fertilizer were the highest under CW275% treatment,while the yield of tobacco leaves under the treatment of CW250% was the highest.In summary,applying citrate acidsoluble potassium fertilizer containing 75% potash fertilizer at the rate of 300 kg/hm2(CW275%)in the tobacco root zone can effectively improve the potassium nutrients,increase the yield,potassium content and potash fertilizer utilization efficiency of tobacco,and achieve high quality and high yield in calcareous soil of Huanghuai tobacco region.