Abstract: Background and Objective: In recent times, interest in early nutrition has increased as a method of mitigating negative effects of delayed access to feed in birds. One of the methods used is in ovo feeding. This study aimed to investigate the effect of in ovo feeding (IOF) of a novel product, Hamlet Protein Avistart (HPA), on hatchability, chick quality and early performance of broiler chicks by using hatching eggs from two strains of broiler breeders. Materials and Methods: The IOF solution was prepared by suspending HPA in Milli Q water, serially diluted from 150-18.75 mg mL–1, heated and centrifuged to obtain the supernatants used for IOF on Embryonic Day (ED) 17. Eggs with live embryo were distributed to seven in ovo feeding (IOF) groups: (control group (intact eggs), sham group (perforated only, SH) and groups injected with either 1 mL Milli Q water (M Q water), 150 (top HPA, T-HPA), 75 (high HPA), 37.5 (medium HPA, M-HPA) or 18.75 (low HPA, L-HPA) mg mL–1 HPA solution in four replicates per strain. Hatched chicks were distributed to the IOF groups and reared till 10 days after measuring hatchability and chick quality. Feed intake, body and visceral organs weight were recorded and samples of jejunum and whole pancreas collected for digestive enzyme activities at 5 and 10 days. Data were analysed separately for each strain by one-way ANOVA using Minitab. Results: Hatchability rate was improved in the M-HPA and the SH groups and lowest in the MQ group. At hatch, body weight and weight of bursa were highest in the T-HPA group in Cobb 500. The HPA solution affected (p<0.05) the shank-to-toe length only in Ross 308. At 5 day, gross responses in chicks improved with higher HPA concentration in the solution, so also the weight of small intestine and gizzard plus proventriculus in Cobb 500 and Ross 308, respectively. At day 10, body weight gain and feed intake were higher (p<0.05) in the SH group and the T-HPA groups, respectively in Cobb 500 broiler chicks. The activity of enzyme was not affected by the IOF treatments. Conclusion: This study showed that the product has potential to improve hatching weight of broiler chicks and early post-hatch performance till 10 days.