In order to improve the production efficiency of slim cigarette, the stability of cigarette physical characteristics and further understand the variations between operating parameters and cigarette making condition, influence of needle roller overfeed, air fan pressure and stem separation air pressure on slim cigarette making machine operating conditions and cigarette physical characteristics were studied by the methods of 3 factors and 3 levels orthogonal design and mathematical statistics. The results are as follows: ① needle roller overfeed, air fan pressure and stem separation air pressure, the three cigarette making machine operating parameters, have different effects on slim cigarette making machine operating conditions and cigarette physical characteristics; ② Needle roller overfeed has significant difference with trimmer disc position, loose and rate and end density amount (P＜0.05); ③ With the needle roller overfeed increased, trimmer disc position decreased, end density amount increased, loose and rate decreased, and content of loss of tobacco from the ends decreased; ④ Air fan pressure has significant difference with trimmer disc position (P＜0.05); ⑤ With the negative air fan pressure increase, trimmer disc position decreased. In summary, with the needle roller overfeed increased, loose and rate of slim cigarette making machine will decreased and the quality of slim cigarettes will be improved.