The aim of the present study was to evaluate the effects of oral administration of essential oils (carvacrol, thyme, and oregano) on anti-immune stress, antimicrobial properties, and repairing the intestinal damage caused by Salmonella enterica lipopolysaccharides (LPS) in broilers. A total of 100 Ross 308 broilers (21-d-old; 1.10 ± 0.11 kg) were randomly allocated to five groups: T1, basal diet + saline; T2, basal diet + LPS; T3, basal diet + 200 μL carvacrol oils + LPS; T4, basal diet + 200 μL thyme oils + LPS; T5, basal diet + 200 μL oregano oils + LPS, with 20 replicates each, and one chicken per replicate per cage. Those challenged by LPS resulted in an immune stress, which manifests as the abnormal growth (P < 0.05) in immune organs, and the content of immunoglobulin G (P < 0.05), tumor necrosis factor-α (P < 0.05), and the rectum temperature (P < 0.05) increased compared with other groups. The oral administration of essential oils controlled the immune stress to a certain extent. The essential oils could reduce harmful bacteria, such as Escherichia coli (P < 0.05) and Salmonella enumeration (P < 0.05), in vivo of broilers. Meanwhile, the essential oils repaired the intestinal damage, which showed a reduction in the villi height (P < 0.05) and goblet cell (P < 0.05) caused by LPS. In conclusion, the essential oils (carvacrol, thyme, and oregano essential oils) controlled the stress reaction and maintained intestinal health to a certain extent.