Abstract：Real-time quantitative PCR (QPCR) allows quantification of starting amounts of DNA, cDNA, or RNA templates. QPCR was based on the detection of a fluorescent reporter molecule that increases as PCR product accumulates with each cycle of amplification. It exceeds the limitations of traditional end-point PCR methods by allowing either absolute or relative quantification of PCR product at the end of each cycle, and avoiding the pollution in traditional PCR. On the other hand, it has such excellences as high sensibility, specificity and accuracy. It has a widely useless in the plant genetic engineering, Microbial and medicine field. In this paper, we reviewed the principle, characteristics, recent advances in fluorescent probe of the real -time quantitative PCR.; and the application of QPCR in plant genetic engineering, Microbial and medicine field were summerized in detail in this paper. In addation, we also predicted the the further application of QPCR in a more popularizated area and gene diagnose.