One hundred eighty 14-d old Japanese quail chicks were individually weighed and randomly distributed into six treatments with three replicates, 10 chicks each. The chicks were reared up to 42 days of age. Cadmium (Cd) in the form of cadmium chloride (CdCl₂.2½ H₂O) was added to the basal diet at 0, 5 and 50 mg/Kg diet with or without 1000 units of phytase supplementation. The results indicated that there was marked reduction in body weight and feed consumption and worse feed conversion ratio for birds fed 50 ppm Cd while slightly reduction was noticed for those received 5ppm compared with the control group. Addition of phytase alleviate completely and partially the adverse effect of 5 and 50 ppm Cd on growth performance, respectively. Linear significant reduction was observed for hematocrit, hemoglobin, plasma concentration of total protein and its fractions, Ca, and P in quail chicks fed Cd contaminated diets comparable to those of control and phytase groups. Conversely, A/G ratio, uric acid, creatinine, AST and ALT were increased, indicating hepatic and renal dysfunction. Supplemental phytase in combination with Cd could eliminate the adverse effect of Cd, depending upon the dose inoculated. Chicks whose diets polluted with either 5 or 50 ppm Cd showed lower humoral immune response at primary and secondary antibody titers than those of control and phytase groups. Therefore, chicks of 5 ppm Cd in blend with phytase was insignificantly different from those of Cd free diets. Significant lower dressing and relative tibia weight was noted for birds exposed to Cd either at low or high level as compared with those of control, phytase and 5 ppm Cd in combination with phytase. Opposite trend was noted for the relative weights of liver, kidney, heart, gizzard and brain. A wide range of histological degenerations and damages were observed in the hepatic and renal tissues of Cd exposed chicks. The magnitude of these lesions was dose dependent. However, normal histological appearance was almost noted as phytase combined with 5 ppm Cd. It could be concluded that phytase supplementation reduce the adverse effect of cadmium on growth performance, hematological and physiological aspects and immune response. However, more researches are needed to determine the optimal level of phytase under different levels of cadmium contamination to achieve normal productive and physiological status of Japanese quails.