Abstract: Tibetan chicken is one of those chicken breeds that could adapt to high altitude and low O2 tension environment; it owes an integrative genetic mechanism for hypoxia adaptability compared to lowland chicken breeds. HIF-1α and HIF-2α are the central factors playing important roles in maintaining organisms’s oxygen homeostasis. In this study, the expression of HIF-1α and HIF-2α genes were investigated by Real Time-PCR in Tibetan chicken and Dwarf chicken embryo brain tissue under normoxia (21% oxygen concentration) and hypoxia (13% oxygen concentration). The results showed that Tibetan chicken always had lower mortality than Dwarf chicken during the incubation. We also detected higher HIF-αs expression at the late of incubation (18th day) compared with that at 12th day in all tested samples; we further obtained the expression pattern of HIF-αs genes in dead embryos was opposite to that in live embryos.