Abstract: 【 Objective 】The purpose of this study is to investigate the effects of fermented Chinese herbal medicines on the growth performance, serum biochemistry and growth hormone of lambs.【 Methods 】A total of 120 15-day-old lambs with similar newborn weight (3.25±0.52)kg in good body condition were selected and randomly divided into 4 groups (3 replicates in each group, 10 sheep in each replicate), 10 sheep in each replicate) and fed lamb starter feed (0 groups), lamb starter feed + 0.2% fermented Chinese herbal medicine (0.2% group), 0.4% fermented Chinese herbal medicine (0.4% group) and 0.6% fermented Chinese herbal medicine (0.6% group) respectively. The test period lasted 45 days.【 Results 】The results showed that: 1) The body weight of the experimental group at 30 days of age was significantly higher than that of the control group (P<0.05). The 60-day-old body weight of the 0.2% and 0.6% groups was significantly higher than that of the 0 group (P<0.05). The 21-25 days of age, 26-30 days of age, and 36-40 days of age in the experimental group were significantly higher than those in the control group (P<0.01). The starter intake (SI) of the 41-45-day-old starting feed in the 0.6% group was significantly higher than that in the 0 group (P<0.01). 2) The contents of anti-tumor factor-α (TNF-α) and interleukin-6 (IL-6) in the serum of lambs in the experimental group were significantly lower than those in the control group (P<0.01). The content of protein (GLB) in the serum of lambs in the 0.6% group was significantly lower than that in the 0 group, 0.2% group and 0.4% group (P<0.05). The serum content of superoxide dismutase (SOD) in the experimental group was significantly higher than that in the control group (P<0.01). The serum levels of total antioxidant capacity (T-AOC) and glutathione peroxidase (GSH-Px) in the 0.4% and 0.6% groups were significantly higher than those in the 0 group (P<0.01). The serum levels of malondialdehyde (MDA) in the 0.4% and 0.6% groups were significantly lower than those in the 0 group (P<0.01).【 Conclusion 】It can be seen that the addition of fermented Chinese herbs to the diet of lambs under the conditions of this experiment can help to improve growth performance, promote the secretion level of growth hormone, increase the body's antioxidant capacity and immune level, thus alleviating the weaning stress of lambs.