Abstract: In order to avoid the over conditioning of tail tobacco in loosening and conditioning cylinder due to tobacco input interruption, the control program and related equipment were optimized via analyzing the reasons causing tobacco interruption. The PLC was reprogrammed to achieve time-delay setting and gradient adjustment of steam injection and water input, the control program for equipment start/stop was also optimized, and a reverse function was added to the belt conveyor at cylinder outlet. The effects of modification were test on the WQ3313 conditioning cylinder, the results showed that when the input tobacco was interrupted, the steam injection flow and water input inside the cylinder decreased gradually. The results of sensory evaluation indicated that the sensory quality of the tail tobacco did not obviously differ from that of the cut tobacco processed regularly, the cut tail tobacco could be used directly to manufacture cigarette. The said method provides technical supports for ensuring cigarette quality consistency between batches.