Abstract: To address the impact of airflow vortices within high-speed rolling bearing cavity on lubrication performance, a functional cage structure was proposed. A 2/14 gas-phase flow field simulation model of the bearing was established to analyze the internal gas-phase flow field of both traditional and functional cage bearings. The influence of the microstructure number in the functional cage on the gas-phase flow field within the bearing cavity was investigated. A transparent inner and outer ring bearing was developed, and a visualization test bench was constructed. The results demonstrate that the functional cage can regulate the gas-phase flow within the bearing cavity, enabling the external oil to be drawn into the cavity. Increasing the number of microstructures,the functional cage can make the air flow velocity enhanced at the narrow end and the airflow vortices eliminated. The study achievement is mainly represented in the significant insights for design of high-speed bearing cage structures and the improvement of bearing lubrication performance.