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Aiming to study the differences between ground channel ventilation (GCV) and ceiling ventilation (CV) in nursery piggery in winter. The effects of GCV and CV ventilation system on the environment of piggery were studied. The field test method was used to test and analyze the thermal environment and air quality environment of piggery with GCV and CV ventilation modes in a largescale conservation farm in Guangxi in winter. The result showed that the thermal environment of GCV piggery was better than that of CV piggery. Although there was no significant difference in average temperature of GCV and CV piggery during the test period （p>0.05), the temperature fluctuation of GCV piggery was smaller than that of CV piggery (1.7℃<4.6℃). GCV piggery underground air duct had heating or cooling effect on fresh air outside the house. When the temperature of fresh air outside the house was lower than 20.2℃, GCV heated the outside air. When it was higher than 20.2℃, GCV cooled the outside air. Although the average ventilation rate of GCV piggery was lower than that of CV piggery, the temperature distribution uniformity of GCV piggery was better than that of CV piggery （p<0.05). The concentration of NH3, PM2.5 and PM10 in GCV piggery was lower than that in CV piggery (p<0.05), and the removal efficiency of gas pollutants in GCV piggery was higher than that in CV piggery (p<0.05). There was little difference in the concentration of gas pollutants in the outlet of the two models of GCV and CV (p>0.05), and the emission rate of air pollutants in GCV piggery was lower than that in CV piggery (p<0.05). The results showed that GCV ventilation system was better than CV ventilation system in nursery piggery in winter.