This research was carried out to evaluate the difference in the mRNA genetic expression of the liver genes as adenine nucleotide translocase (ANT), cytochrome oxidase subunit III (COX III), Insulin like growth factor binding protein 2 (IGFBp2) and Avian uncoupling protein (Av UCP), as well as growth performance include (body weight and body weight gain ) between Cobb broilers and Fayoumi native breeds. 120 females of one-day-old Cobb and Fayoumi chicks had been used. Chicks were distributed equally in three replicates. the results showed that, expression of adenine nucleotide translocase (ANT) had non-significant difference between cobb and Fayoumi (P > 0.05) but there was significant difference in COX III, IGFBp2 , Av UCP gene expressions and body weight, body weight gain between cobb and Fayoumi breeds.(P