Abstract: To study the effect of different air inlet angels of heat recovery ventilation system on the heating of the swine pens, the air temperature field and airflow field in the empty swine pens were numerically simulated based on computational fluid dynamics and theoretical model was validated with experiments. The experimental results showed that simulated and experimental results had the higher fitting degree and the theoretical model was reasonable. And when the ventilation rate of swine pens was met the requirement of, air temperature field and airflow field were numerically simulated with different air inlet angel (30°、45° and 60°) of the heat recovery ventilation system based on above model. The results showed that compared with both 30° and 60°air inlet angel, the air temperature was more even and fresh air was mixed more sufficiently inside the swine pens with the 45°air inlet angel, which met the growth requirement of pigs. It can provide a reference for application of heat recovery ventilation system in pig production.