This study investigated the effect of injecting biotin, and carnitine in hatching eggs at four incubation times on hatchability traits and subsequent broiler chick's performance. The eggs were injected with 0.1 ml biotin or carnitine compared to of saline (placebo control) at 1, 14, 16, 18 days of incubation. Thereafter, bird's growth performance was monitored. The obtained results show that the highest fertile hatchability percent was achieved by saline water followed by biotin and carnitine injection. The best fertile hatchability percent recorded with the injection at day 18followed by day 14, day 16 of incubation. Biotin followed by carnitine injection significantly improved final live body weight of chicks compared to saline water. Also, biotin injection significantly showed the best feed conversion ratio. Injection time had no significant effect on growth performance and carcass traits. It is suggested that the eggs injection with biotin or L-Carnitine at the day 18^th of incubation could improve hatchability and subsequent broiler growth performance.