Abstract: To further learn the mechanism of yarn formation of rotor spinning, the air flow field in spinning channel should be analyzed. The air flow field in spinning channel was studied by FLUENT and the simulation results reveal the airflow characteristics in rotor spinning channel as: there is negative pressure in the rotor and the value existed in the exit of fiber pipeline is the minimum; great pressure is focused on the accumulation groove near the exit of fiber pipeline, arousing the unbalanced force on the rotor; the airflow speed in the exit of fiber pipeline is faster than others, and after entering rotor the vortex is produced and the speed decreases gradually along the rotor; the airflow along the rotor flows towards the exit of rotor after about 90 degrees rotation and the trend of backflow is generalized; when the degrees of the slip plane are more than 27, the airflow characteristic alters negatively, which proves that the degrees of the slip plane should not be designed to be over or equal to 27.