The invention relates to the technical field of mosquito repelling and 
insect preventing sachets and specifically relates to a mosquito repelling and 
insect preventing sachet which is prepared from the following ingredients: rhizoma nerdostachyos, rhizoma kaempferiae, herba lysimachiae foenum-graeci, 
borneol, 
camphor, rhizoma acori graminei, Chinese 
mugwort herb, herba asari and 
semen zanthoxyli.The invention further discloses a preparation method of the sachet. The preparation method comprises the steps of treating all the ingredients; then mixing and stir frying the treated rhizoma nerdostachyos, the treated rhizoma kaempferiae, the treated herba lysimachiae foenum-graeci and the treated herba asari, cooling and mixing with the 
borneol, the 
camphor, the rhizoma acori graminei, the Chinese 
mugwort herb and the 
semen zanthoxyli; smashing, sieving and filling into a sachet bag to obtain the sachet. The sachet disclosed by the invention has the advantages of pleasant fragrance, high 
user acceptability, more obvious 
insect preventing effect and no toxic and 
side effect. The sachet can prevent insect and mould. The rhizoma nerdostachyos in the sachet has the advantages of light 
flavor, durability and thickness, so that the rhizoma nerdostachyos can make 
flavor of all the herbs be released slowly for a long time.