The invention discloses plant pyrus pyrifolia Nakai. fragrant oral cavity atomized liquid and a preparation method. The preparation method comprises the following steps of S1, purchasing qualified pyrus pyrifolia Nakai., a sodium chloride solution of 0.9%, liquor nitrofurazoni of 0.02%, radix scutellariae, Chinese cinnamon, rhizoma cimicifugae, mint and lemons from regular shops; S2, cleaning components of the pyrus pyrifolia Nakai., the radix scutellariae, the Chinese cinnamon, the rhizoma cimicifugae, the mint and the lemons, and after cleaning, placing the cleaned components in a drying room for drying; and S3, respectively crushing the pyrus pyrifolia Nakai., the radix scutellariae, the Chinese cinnamon, the rhizoma cimicifugae, the mint and the lemons, which are dried in S2, after mashing, performing screening with a screen mesh, and preparing fine powder. The plant pyrus pyrifolia Nakai. fragrant oral cavity atomized liquid is simple to make, the sodium chloride solution of 0.9%and the liquor nitrofurazoni of 0.02% are added, so that the effect of sterilizing can be achieved, and the plant pyrus pyrifolia Nakai. fragrant oral cavity atomized liquid is good in oral cavity cleaning effect; and the pyrus pyrifolia Nakai., the radix scutellariae, the Chinese cinnamon, the rhizoma cimicifugae, the mint, the lemons and the like are also added, so that the smell is fresh, people feel comfortable when smelling the plant pyrus pyrifolia Nakai. fragrant oral cavity atomized liquid, and the plant pyrus pyrifolia Nakai. fragrant oral cavity atomized liquid is free from side effects.