Objective To investigate whether the genetically modified somatic cells can survive and express foreign gene for a long time after being transplanted into avian embryo． Methods Chicken DT40 cells as a cell vehicle for delivering foreign protein were transfected with the green fluorescent protein ( GFP) gene，and were introduced into early chicken embryos via blood vessel microinjection at 65 ～ 70 h of incubation at 38. 5 ℃ ． The manipulated eggs were continued to incubate at same condition． The chimerisms of the transplanted DT40 cells were preliminarily observed under fluorescence microscopy at the different stages in the embryos and the hatchlings． Meanwhile，the chimeric positions of the donor DT40 cells and the expression of GFP were further examined by polymerase chain reaction ( PCR ) and immunohistochemistry． Results The results showed that fluorescent-labeled DT40 cells embed in the different organs of the recipients including brain，heart，liver，etc． and can survive before chicken hatch and the GFP gene can be expressed normally． Conclusion Long-term survival of the donor DT40 cells in recipient and normal expression of the GFP gene imply that this approach can be explored for continuous production of target protein in the host chicken，which may provide a basis for avian immune tolerance research and the production of bioreactor．