A straight run experiment was used to investigate the effects of water administration of lyophilized bacterial lysates Broncho-Vaxom® on performance, blood biochemical, antioxidative status and humoral immune response of growing and laying Japanese quail. At the fattening trial, 400 -21-day-old quails were allotted equally into two experimental groups (eight replicates each); the first served as a control and the second received 3.5g Broncho-Vaxom®/ 4L drinking water. The same arrangement was sustained in the laying trial except the reduction of initial number to 160 female quails in each group.No significant alternations were observed in growth performance traits at the end of fattening trial. However, prolongation of treatment time revealed the enhancement effect of Broncho-Vaxom® on final body weight, ovary index and egg production performance. Yolk (%) and yolk-to-albumin ratio were significantly increased, while, albumin (%), egg shape index and Haugh unit were decreased in Broncho-Vaxom® group. Serum liver enzymes and uric acid levels were reduced, while serum concentrations of T₃ and HDL-cholesterol were elevated in Broncho-Vaxom® group at the end of growing trial. None of the aforementioned parameters were affected by the treatment at the end of laying trial. Antioxidant status was significantly improved only at 42 days of age, while total antibodies against-NDV and IgG were improved while IgM was not affected at 42 and 98 days of age. In conclusion, administration of bacterial immunostimulant Broncho-Vaxom® enhanced laying productive performance, egg quality, antioxidant status and humoral immune response of Japanese quail at the end of growing and laying periods