The invention discloses a method for fast, simply and conveniently extracting active citrus yellow vein clearing viruses. According to the method, diseased or infected plant tissues are ground in liquid nitrogen; an extraction buffer solution is added for homogenation; filter liquid filtered by gauzes is subjected to ultracentrifugation at 4 DEG C; supernatant liquid is subjected to ultracentrifugation after being filtered by an Miracloth filtering film; an obtained coarse extraction solution is mixed and is then subjected to ultracentrifugation; virus particles with ultrahigh infection capability are obtained. The virus extraction can be completed within 5h by the method; in addition, various orange varieties can be efficiently infected; the extracted viruses can be applied to the preparation of high-specificity antiserum, pathogenicity identification and virus feature analysis and resistance variety testing. The method has the advantage that the activity of the citrus yellow vein clearing viruses can be simply, conveniently, fast and efficiently maintained.