Cells in the same tissue often have similar structures and functions. However, it is found that each cell is heterogeneous by sequencing cells. Single-cell whole-genome amplification technology is the premise of single-cell sequencing. This technology can be used to reveal the differences of single-cell genomic structures and it also plays an important role in tumor research, developmental biology, and microbial research, and it has already become one of hotspots in life science research technology. The difficulty of single-cell whole genome amplification techniques lies in the isolation of single cells and the amplification of whole genomes. This paper introduces the popular single-cell separation technology and single-cell whole genome amplification technology and also compares the advantages and disadvantages of each technology. The application of the technology in tumor research, developmental biology and microbiology research was also emphatically discussed.