Abstract: High dust concentration and temperature of exhaust gas result in pipeline jam in CTD(Comas tower dryer),therefore a cyclone dust collector with water spraying was designed by using water as cooling medium, high temperature dust particles were captured during water spraying. The optimal injection parameters determined by orthogonal experiments were the distance between nozzle and the top of cyclone dust collector L=30 mm,nozzle angle β=60° and nozzle orifice diameter d=0.5 mm. A three-stage filtration water tank was designed for water recycling. The results showed that: after the application of the designed dust collector,the dusts in exhaust gas settled in site,the SD of moisture content in cut tobacco out of CTD decreased from 0.35 to 0.25, the Cpk value increased from 0.96 to 1.42. The frequency of pipeline cleaning reduced from 1 time/month to 1 time/year. Exhaust gas pipeline jam was avoided effectively.