OBJECTIVE: To establish a technology of preimplantation genetic diagnosis. METHODS: Intracytoplasm sperm injection and blastomere biopsy were performed on two women at the advanced age with the fallopian tube obstruction. Normal embryos were selected for embryo transfer after fluorescence in-situ hybridziation in biopsied blastomere. RESULTS: The levels of serum HCG were increased 20 days after embryo transfer and ultrasonography in 16 gestation weeks showed the fetal growth and structure are normal. CONCLUSION: Two successful clinical pregnancies achieved after preimplantation genetic diagnosis.