The invention discloses a kit and extraction method for rapidly and conveniently extracting
viral DNA from
body fluid. The kit comprises four components, wherein a first component comprises 2mol / L-6mol / L of guanidinium
isothiocyanate, 0.5%-12% of TritonX-100, 10mmol / L-300mmol / L of
tris(
hydroxymethyl)aminomethane and 5%-15% of PEG4000; a second component contains 1mmol / L to 50mmol / L of
sodium dihydrogen citrate, 0.005mmol / L to 0.05mmol / L of
tris(
hydroxymethyl)aminomethane, 5% to 30% of PEG4000 and 0.005% to 0.05% of magnetic beads; a third component contains 10mmol / L to 200mmol / L of
sodium dihydrogen citrate and 1% to 10% of TritonX-100; and a fourth component comprises
mineral oil. The method for extracting
DNA by using the kit can enter a PCR link through splitting
decomposition / combination and cleaning, and compared with a conventional
magnetic bead extraction method, required manual operations and
waiting time are less; a
reagent applied to extraction is efficient and safe, and thus, the harm to a
human body is avoided to the greatest extent; and the sensitivity is further improved as the
DNA in a sample can be completely applied to PCR amplification.