This study was conducted to evaluate the effect of using feed additives in Sasso broiler chicks as growth promoters on productive performance, digestibility coefficient of nutrients, blood indicates, carcass and gastrointestinal measurements and economic return. A total number of 120, one - day old, unsexed Sasso chicks were assigned randomly to four groups. Each group included three replicates. The first group was kept as control and fed the basal diet. The 2nd, 3rd and 4th groups were fed the basal diet (+ 1.00 g Frazyme), (2.50 g mannan oligosaccharides) and (1.00 g Frazyme + 2.50 g MOS)\ kg diet respectively during whole experimental period (1-58) days of age. The obtained results showed that the better (P<0.05) values of LW, WG and FCR were recorded to group four followed by group three at the end of experimental period. There were no significant differences among all experimental treatments in feed intake during the whole experimental period. Significant (P<0.05) improvement has been recorded in digestibility of CP and CF for group four and two respectively. Group four showed the highest values (P<0.05) of breast yield and spleen weight compared to other groups. There were no significant differences of gastrointestinal lengths among all experimental groups Regarding blood parameters, broilers in group two had significantly (P<0.05) Hct, Lipase and Amylase. While, group four broiler's were recorded the highest (P<0.05) TP, Alb., Hb and TAC compared to others. The chemical analysis of meat revealed that greatest (P<0.05) CP of breast meat for group four. However, Thigh meat analysis for birds in control and group four achieved high significant values of fat and ash contents. The lowest mortality and highest PI and economic efficiency were related to groups four and three respectively. On the basis of these results, it can be concluded that adding enzymes combination, MOS or their mixture (Enz+MOS) as feed additives were suitable and had good role in improving productive and economic efficiency of Sasso broiler chicks.