A total number of 400 unsexed one day-old Japanese quail chicks (Coturnix coturnix japonica) were used to study the effect of feeding system on performance of growing quail. Quail chicks were randomly distributed into 4 equal experimental groups of 100 chicks each. Every group was sub-divided into four replicates (25 chicks/ replicates). The first group wasfed on a dietcontaining 24 % crude protein only as  starter diet during the whole experimental period (0-6 weeks of age).Group 2 was on a fed starter diet ( 24% CP) for the four weeks and then switched to the finisher diet      (22% CP) for the last 2 weeks. Group 3 was fed on starter diet ( 24% CP) for the two weeks and then switched to on a finisher diet (22% CP) for the last 4 weeks. Group 4 was fed a diet containing 22 % crude protein as finisher diet only of during the whole experimental period (0-6 weeks of age).The experimental diets were formulated isofibrous and isocaloric (2900 kcal ME/kg). The main results obtained could be summarized as follows: - Live body weights and body weight gain during the whole experimental period was significantly varied (P<0.05) among the experimental groups. Group 2 for the four weeks and then switched to the finisher diet for the last 2 weeks) recorded the highest live body weight and body weight gain. - Feed intake (g) during the whole experimental period (0-6 weeks) was  increased by G4 (fed finisher diet only 22 % CP). Feed conversion ratio (g feed/g gain) were improved with the G2 (starter diet for the four weeks and then given the finisher diet for the last 2 weeks), while it is became worst by G4 (fed finisher diet only 22 % CP). - Protein intake(g) was increased by G1 (fed starter diet only 24% CP) recorded a highest values, while, the G4 (fed finisher diet only 22 % CP) recorded lower ones. Best protein efficiency utilization ratio was obtained with the G2 during the experimental period (0-6 weeks of age). - Different growing period for quail recorded a non significant differences in all carcass traits. - Digestibility coefficients of DM, OM, CP, CF %, the nutritive values expressed as DCP, TDN % and ME (kcal/kg) were significantly (P<0.05) decreased among the experimental diets. However, digestion coefficient of NFE and EE was not significantly influenced by the different diets. - Serum TP, AL, Cr and uric acid recorded a non-significant differences between quail groups, while serum AST, ALT enzymes recorded ones varied (P<0.05) among the experimental groups. - The group 2 (starter diet 24 % CP) for the four weeks and then given the finisher diet (22 % for the last 2 weeks) showed the best net return as well as the highest value of economic efficiency among all experimental groups. - Results obtained in the present study, indicated that a starter diet with moderate protein level (24 % CP) for the four weeks and then given a finisher diet (22 % CP) for the last two weeks in the growing quail period had no adverse effect on growth performance and carcass quality. This system of feeding resulted in an improvement in economic profitability efficiency.