Abstract: Abstract: Cold stress of livestock easily occurs in open sheds of cold areas during winter, due mainly to the relatively low thermal insulation under the low temperature conditions. As such, cold drinking water can further deteriorate the health and growth of young livestock. The objective of this study was to investigate the effect of drinking warm water in winter on the health and growth performance of weaned rabbits. A total of 180 weaned rabbits (47 days of age) with similar body weight (initial body weight 1.2±0.1 kg) were randomly assigned to two groups, either warm water (WW) or cold water (CW) (90 rabbits in each group). An electrical heating wire was also used to heat the warm water, where the water pipe was covered with insulated foam coating. A thermostatic controller was selected to remain at a constant temperature (35.5 ± 1.1 ?C) during the experiment. The cold water was prepared at (5.8 ± 2.3)?C without heating. A 48-day test was carried out to measure various indicators. The results showed that: 1) The indoor average air temperature was (8.9±3.2)℃ during the experiment. The average daily weight gain of rabbits in warm water group was significantly higher than that in cold water group during 47-58 days and 47-94 days, respectively, by 15.11 kg/d and 1.94 kg/d (P<0.05).. 2) The feed-weight ratio of rabbits was significantly lower in the warm water group than that in the cold water group during 47～58 days (18.2%) (P < 0.05). But there was no significant difference during the rest. In addition, the risk of diarrhea in rabbits drinking warm water was significantly reduced by 25.6% during 47～94 days (P < 0.05), compared with the cold water group. The expressions of thyroid hormone receptor α and β (THR α and β) in jejunum were significantly down-regulated on 70 days in rabbits drinking warm water (P < 0.05). 3) The contents of immunoglobulin A (IgA) and total protein (TP) in serum increased significantly for the rabbits drinking warm water, with the increase of age, especially on 82 days (P < 0.05). Moreover, the abundance of Roseburia increased in the cecum of rabbits on 82 days in the warm water group, relating to nutrient digestion and absorption, indicating 6.9 times higher than that of 58-day old rabbits (P < 0.05). Consequently, the constant temperature drinking system in the open sheds in winter can be expected to improve the immunity, intestinal digestion, and absorption capacity, thereby promoting the growth and health of weaned rabbits. The finding can provide theoretical support to improve the survival rate and production efficiency of weaned rabbits in open houses in cold areas.