Abstract: In order to study the flow characteristics of buoyancy-inducing airflow in the Trombe wall channel in high-rise buildings,the comparative analysis of the induced airflow characteristics in Trombe wall channel in a two-story building were carried out. The reliability of the simulation method is verified by combining experimental research and numerical simulation. The same numerical simulation method was used to optimize the flow state of buoyancy-induced airflow in a 24-story building Trombe wall channel. The results show that by setting triangular guide ribs in the channel passage,air flow condition can be improved and the ventilation effect of the connected passage is significantly better than that of the separate passage. In the connected channel, the ventilation ribs have the best ventilation effect when the guide rib size is 3/4 of the channel width.