The invention discloses a lysate, nucleic acid extraction kit, and nucleic acid extraction method for nucleic acid extraction. The lysate for the nucleic acid extraction is prepared from 0.5 to 2M ofsodium salt, 2 to 5M of guanidine salt, 1 to 5mM of a metal ion complexing agent, 0.25% to 1% of a nonionic surfactant, and 1% to 3% of PEG, and the molecular weight of the PEG is 6000 to 10000 Da, preferably 8000 Da. The lysate has a reasonable ratio, cells can be fully and effectively lysed, the lysis efficiency is high, so that the nucleic acids in the cells can be fully released, and the nucleic acids with higher concentration and purity can be obtained, and the quality and extraction efficiency of the nucleic acids are improved advantageously; and according to the lysate and the kit, digestion and removal of protein can be conducted without the aid of proteinase K during the entire nucleic acid extraction process, alcohols are not usedfor precipitate the nucleic acids,the obtained nucleic acids have high purity, and fragments are complete.