The invention discloses a quick extraction method of plant genomic DNA (Deoxyribonucleic Acid). The quick extraction method is characterized by comprising the following steps of (1), taking a plant tissue sample, adding liquid nitrogen, grinding the plant tissue sample into powder and collecting into a centrifugal tube, and the like. SDS (Sodium Dodecyl Sulfonate) in a Buffer A in the quick extraction method can be used for cracking a cell membrane to denature protein; a Buffer B can act with the SDS; impurities of the protein, a polysaccharide and the like can be effectively removed; moreover, PVP40 (Polyvinyl Pyrrolidone 40) in the Buffer A can be used for effectively removing substances of the polysaccharide and polyphenol in plant tissue; the purity of the DNA is improved; the completeness of the DNA is enabled to be better; the quick extraction method can be directly used for a PCR (Polymerase Chain Reaction) and various enzyme digestion reaction; meanwhile, the quick extraction method does not need to use organic solvents of phenol chloroform and the like in the entire extraction process; therefore, steps of ethanol precipitation and the like do not need to be carried out; the extraction method provided by the invention, compared with a conventional extraction method, can be used for more quickly, simply and conveniently extracting the DNA; the operation, on a single sample, of the quick extraction method can be completed within 1 hour and the extraction time is greatly shortened.