Abstract: Not satisfied with its accuracy, the automatic flavoring control system in HAUNI primary(processing) line was improved.The factors which caused the accuracy fluctuation were: the generation of(reflux) error and the variation of flavor components.Reflux was avoided by: 1) modifying the way of pump bypass;2) controlling the flow of cut tobacco after mixing;3) adjusting the parameters setting in frequency converter.The variation of flavor components was controlled as well, and the electromagnetic flow-meter was replaced by mass flowmeter.After improving, the flavoring error was mostly below 2%, and the error of > 1% was less than 12.5%, the flavoring metering accuracy improved obviously.