Abstract: The effects of experimental conditions,such as extracting solvent,alcohol concentration,ratio of material to liquid,extracting time,pH value of extracting solvent,and condition of adsorption-desorption by HPD-400 macroporous resin,on the extraction and separation of chlorogenic acid from waste and sub-standard tobacco were investigated.The results showed that:1)the appropriate conditions of extraction assisted by ultrasonic were extracting solvent 30%(pH 4)ethanol,ratio of material to liquor 1:10,extraction time 45 minutes;2)the chromatographic conditions for the extracted solution of chlorogenic acid were HPD-400 macroporous resin column;42.5 mL of extracted chlorogenic acid solution at a concentration of 4.0 mg/mL,flow rate 1.42 mL/min;elution solution 191.7 mL 30% ethanol.Under the said conditions,0.335 g solid material containing chlorogenic acid of 31.9% was obtained from 10.1 g of tobacco,the yield of chlorogenic acid was 1.71% and the chromatographic recovery of chlorogenic acid reached 72.3%.