Abstract: he genetic tests of the preimplantation human embryo mainly include： preimplantation genetic diagnosis（PGD） and preimplantation genetic screening （PGS）. PGD based on PCR and FISH has been used to detect the single gene disorders and inherited chromosome abnormalities for the last 20 years. PGS with the same technology in PGD was used to detect aneuploidy chromosomes in embryos, to select those embryos with normal chromosomes for IVF transfer. It has been applied in those patients of advanced age，repeated implantation failure，repeated miscarriages and severe male factor infertility. There are dramatic changes in the PGD methodology. Both array-comparative genomic hybridization and single nucleotide polymorphism arrays have been introduced into clinical practice for PGD and PGS. In this review，we introduced some new methods and controversies in the field of PGD/PGS.

Key words: Preimplantation genetic diagnosis, Preimplantation genetic screening, Embryo biopsy, Diagnosis