The problems existing in the conventional gene therapy involves low effectivity in virus′ targeting transduction, low speciality in integration, low effectivity in controlling the gene expression dosage and immunogenicity of virus vector. While most single gene genopathies can be cured by correct the single mutant nucleotide using gene therapy, without changing the whole gene. Chimeraplasty is a tool for site-specific gene repairing which developed rapidly in recent years. The RNA/DNA chimeric oligonucleotide can located to the exact site and repair the wrong base in situ by complementing to the host chromosome DNA sequence，and it can also be used to produce targeted mutation. It has been successfully applied in the gene therapy of some single gene genopathy and plant genetical modification. The principle, examples and prospect of this technique was described.