The effects of thyme oil on meat quality in Japanese quails were investigated. A total of 192 mixed sexes Japanese quail chicks were used in the feeding trial, which lasted until the birds reached 35 d of age. Birds were randomly allocated to 4 dietary treatments comprising three experimental groups and one control group (basal diet). Each group was divided into 4 subgroups, with each containing twelve quails. Basal diet was formulated according to NRC recommendations. Thyme oil was added daily to the basal diet at 200 (T1), 400 (T2) and 600 mg/kg (T3) levels, respectively. After slaughtering and evisceration, the carcasses were stored at 3 +/- 0.5 degrees C for 10-12 h and then the breast fillets were removed from carcass.