This study aimed to evaluate the beneficial role of chamomile essential oil in improving productive and reproductive performances, egg quality, and blood metabolites and reducing the toxic effect of Ochratoxin A (OTA) in quail breeder's diets. A total of 144 mature quails, 8 wk old, were divided into 6 groups. The treatments were: G1 (the control), G2 (supplemented with OTA 1 mg/kg diet), G3 (supplemented with chamomile oil 0.5 g/kg diet), G4 (supplemented with chamomile oil 1 G/kg diet), G5 (supplemented with OTA 1 mg/kg diet + chamomile oil 0.5 g/kg diet), and G6 (supplemented with OTA 1 mg/kg diet + chamomile oil 1 g/kg diet). The OTA administration alone significantly decreased egg production and mass in quail breeders (P < 0.0001). Moreover, poor feed conversion ratio (FCR), fertility percentage (P < 0.0001), and hatchability percentage (P < 0.0009) were recorded. A significant decline (P < 0.05) in the levels of serum protein (total protein and globulin) was also recorded in OTA-contaminated groups, along with elevated serum levels of liver enzymes such as alanine transaminase (ALT) and Aspartate transaminase (AST) and kidney function test as urea and creatinine levels (P < 0.05). Ochratoxin A-contaminated feed resulted in a significant elevation (P < 0.05) in total cholesterol (TC), triglyceride (TG), low-density lipoprotein (LDL), and very low-density lipoprotein (VLDL), along with a significant reduction (P < 0.05) in antioxidant status and immunological response. The supplementation of chamomile essential oil, either 0.5 g/kg or 1g/kg, to the basal diet or OTA-supplemented feed, revealed a significant increase in hatchability %, fertility, egg mass, and egg production and better FCR, egg quality, and immunological status when compared to OTA only. Moreover, chamomile essential oil supplementation improves liver and kidney function markers, decreases LDL, VLDL), TG, and TC. Along with a significant increase (P < 0.05) in terms of antioxidant status as glutathione peroxidase enzyme (GPX), total antioxidant capacity (TAC), and superoxide dismutase (SOD) and significantly (P < 0.05) improves immunological response as IgM, IgG, lysozyme and complement 3. In summary, chamomile oil supplementation, either separate or combined with OTA, reduced the adverse effects of OTA and led to improved productive and reproductive performance, egg quality, and blood metabolites in Japanese quail breeders.