Abstract: In order to alleviate the contradiction between heat preservation and ventilation in the closed house in winter, in the experiment, the ventilation effect and heat recovery performance of heat recovery ventilation system installed in the brood house were evaluated. The environmental conditions in the house under these two ventilation modes were analyzed by measuring the temperature, humidity, concentration of harmful gas NH₃ and CO₂, and performance of heat recovery system in different locations and at different times in the house, and the performance of the heat recovery ventilation system and the effect of its application in the brooding house in winter were explored. The results showed that the average daily temperature in the experimental group was significantly higher than that in the control group（P＜0.05）; the average daily humidity was significantly lower than that in the control group（P＜0.05）, and the temperature and humidity in the control group fluctuated greatly in a short period of time, which was not conducive to the growth of chicks. In the vertical direction of the chicken house, both groups showed a rule that the temperature of the upper layer was significantly higher than that of the lower layer, but the temperature difference between the upper and lower layers of the test group was smaller than that of the control group. The temperature and humidity changes in the horizontal direction in the experimental group were relatively small, while the changes in the control group were relatively large. In both groups, the temperature on the west side was significantly higher than that on the east side（P＜0.05）, and the humidity on the west side was significantly lower than that on the east side（P＜0.05）. Compared with the control group, the average concentration of NH₃ was significantly reduced by 0.4 mg/m~3（P＜0.05）, and the average concentration of CO₂ was significantly increased by 609 mg/m3（P＜0.05）. The NH₃ and CO₂ concentrations in the two groups showed an increasing trend from the west to the east, but both concentrations did not exceed the limits set by the environmental quality standards for brooder houses. The actual air volume of the heat exchanger was 45% to 55% of the rated air volume. The heat exchange efficiency was 70.03%-74.20%, the maximum heat recovery could reach 12 260 J/s, and the COP range was 6.3-14.6, which had an energy-saving effect. The results indicated that the heat recovery ventilation system could recover the heat in the old wind and preheat the new wind, which effectively alleviate the contradiction between heat preservation and ventilation in winter.