Abstract: For making super slim cigarette with the diameter of 5.4 mm, the suction chamber assembly in ZJ114 cigarette making machine was modified: 1) redesigning the inner profile of the shoe;2) according to the position of right and left guides and trough rail, drawing the working curve for trough assembly installed according to the parameters, and verifying the data with population standard deviation;3) redesigning the suction band, top rail, bracket and related parts;4) connecting the suction chamber motor with a frequency converter to adjust the motor's frequency timely.The modified machine makes qualified super slim cigarettes 5.4mmin diameter successfully and runs stably and reliably.