This study evaluated the effects of dietary butyric acid (BA) on the Japanese quail' performance, immunology, lipid profile, cecal microbiota, and antioxidant levels. 250 unsexed, one-week-old quail chicks were divided into 5 groups, each with fifty chicks (5 replicates of 10 chicks). The first group was given the basal diet (BD), while the 2nd to 5th groups were fed BD with 50, 100, 150, and 200 mg BA/kg, respectively. The results indicated that BA improved weight gain and FCR (p < 0.05) and decreased total FI. The 200 mg BA/kg of diet showed the lowest FI (p < 0.05) and the best FCR (p > 0.05). BA boosted immunity through increasing IgA, IgM, IgG, and Complement 3. Significantly lower alanine aminotransferase (ALT), aspartate aminotransferase (AST), and lactate dehydrogenase (LDH) were observed at 150 and 200 mg BA/kg (P < 0.05) than the control group. The BA-supplemented quail showed lower total cholesterol (TC), triglyceride (TG), low-density lipoprotein (LDL), and very low-density lipoprotein (VLDL) than the control one. This effect was more pronounced for 100 and 200 mg of BA/kg. However, high low-density lipoprotein (HDL) did not differ from the control group (p > 0.05). BA at ≥100 mg/kg diet reduced malondialdehyde (MDA) and induced greater levels of superoxide dismutase (SOD), total antioxidant capacity (TAC), glutathione peroxidase (GPX), globulin, total protein, digestive enzymes than the control group (P < 0.05). BA decreased cecal E. coli, Salmonella, Enterococcus, and Coliforms and increased Lactic acid bacteria (p < 0.05) compared to non-supplemented group. Collectively, the inclusion of 100 mg BA/kg diet is ideal for Japanese quail production and health.