Abstract: In order to promote the transferring smoothness and product quality, the negative pressure passages for filter assembling in ZJ119-MAX were studied with computational fluid dynamics (CFD) method, and the distribution of air flow in the passages was investigated. On the basis of their original structure, the negative pressure passages were simplified, and the areas which were not closed were reconstructed partially and divided into grids. A CFD model for the negative pressure passages was developed by adopting unstructuralized tetrahedral grid and Realizable k-ε model of turbulence, and then the streamline, pressure distribution and turbulent dissipation in the passages were simulated and analyzed. The results showed that the air moved in the passages fluently in general; however, variation of airflow velocity and turbulent dissipation at air inlets, adverse pressure gradient in divergent pipes, and vortex at the corner areas consumed more energy. The air movement in the turning drum system could be promoted by optimizing the air inlets in filter and cigarette feeding systems and adding a passage connecting the negative pressure passages of filter and cigarette feeding systems and rolling system. These findings provide technical supports for optimizing the design of filter assembler and improving its working efficiency.