Top combustion regenerative hot air stove has a wide application prospect because of the following advantages: large heat storage area, high strength structure, high thermal efficiency, high hot air temperature, low maintenance costs and long life. Now, most researches about hot air stove focus on the structure optimization, flow structure improvement and further increasing hot air temperature. In this study, a thee-dimension mathematical model was built to simulate the flow field in bottom zone of hot air stove, understand the flow theory as the fluid pass the support pillar. Furthermore, several different structure dam-boards were designed, and the influence of the different structure to the flow field was analyzed. The results of this study enrich the top combustion regenerative hot blast stove theory, and provide the theoretical reference for the top combustion hot blast stove structure optimization, increasing the hot air temperature, saving energy and protecting environments.