In order to investigate the effects of online laser perforation parameters on physical and chemical indexes of fine cigarette, the cigarette samples were prepared with different laser perforation positions, different hole numbers and different laser perforation time, and the relationships of the said parameters were also analyzed with cigarette ventilation rate,the consistence of ventilation rate and the deliveries of routine smoke constituents. The results showed that: ① Compared with normal cigarettes, the positions of online laser pulse had little influence on physical and chemical indexes of fine cigarette, the change of physical and chemical indexes of fine cigarettes with different positions was smaller, while the ventilation rate was the highest in the middle of the filter (14 mm from the lip end), and the minimum amount of mainstream smoke was released. ② Laser pulse hole number and time could affect physical and chemical indexes of fine cigarettes obviously, the mean value of ventilation rate increased with the increase of hole number and laser pulse time, meanwhile, the amount of mainstream smoke emission decreased significantly. The suitable ventilation rate and smoke index could be obtained by adjusting the parameters of online laser perforation of fine cigarette.