Abstract: In order to promote the performance of S400 tobacco reclaimer and the structure of reclaimed cut tobacco, its heating and humidifying system and separating system were optimized and modified.The optimal parameter combination was determined with experimental design method.The optimal testing conditions were:bottom belt frequency 41 Hz, the first stage fan motor frequency 58 Hz, the second stage fan motor frequency 51 Hz, steam pressure 0.2 MPa.The results showed that:1)Cut tobacco reclaiming rate increased from 50.79% to 65.44%, and the long strand proportion in reclaimed cut tobacco raised from 62.54% to 74.48%.2)On the premise of ensuring the reclaiming rate and long strand proportion of cut tobacco, the rate of tobacco in paper and the purity of and moisture content in reclaimed cut tobacco met the relative requirements.The mentioned method provides technical supports for improving the structure of reclaimed cut tobacco and reducing consumption.