Previous studies on exploring the effect of potassium fulvic acid in tobacco were mainly based on basal application，and the dosage was large，which replaced part of the potassium fertilizer by the way.However，the price of potassium fulvic acid is high，and the water solubility under the current process is getting better and better，irrigation has become an economically efficient way of applying potassium fulvic acid.In this study，‘Yunyan 87’ was took as the test material，the amount of potassium fertilizer was determined and then the fertigation of low dosage potassium fulvic acid on the appearance quality，sensory quality，chemical indexes and economic characteristics of flue-cured tobacco were explored in Enshi area.The results showed that the application of potassium fertilizer(K2O)270 and 405 kg/hm² treatments had higher effects on the chemical properties of tobacco leaves，such as sugar-alkali ratio，nitrogen-alkali ratio，potassium-chloride ratio，and economic traits such as output value，medium and upper tobacco rate than the 135 kg/hm² treatment.The effect could be better when the local potassium fertilizer application rate increased by 45 kg/hm² according to the one-dimensional quadratic effect equation of potassium fertilizer application rate and flue-cured tobacco output value，combined with the chemical composition of tobacco leaves.Compared with the 315 kg/hm² polassium fertilizer treatment，the combined application of 15 or 30 kg/hm² potassium fulvic acid improved the coordination of the intrinsic chemical composition of tobacco leaves，improved the appearance quality index and sensory quality of tobacco leaves，and finally increased the output value of tobacco leaves by 23% and the rate of medium and upper grade tobacco by 1 percentage point，compared with conventional fertilization.Based on the yield and quality of tobacco leaves，it was recommended to fertigation 25 kg/hm² potassium fulvic acid on the basis of the potassium fertilizer dosage of 315 kg/hm² in Enshi area.