The invention discloses a method for preparing a Chinese herbal medicine disinfectant for abating air pollution through an air purifier. The method comprises the steps: mixing all formula raw pharmaceutical materials such as 30g of folium isatidis, 16g of herba leonuri and the like, loading the mixed raw pharmaceutical material to an extracting tank, adding 600L of water into the extracting tank, carrying out heated extraction for 2 hours, obtaining distilled aromatic water from the top of the extracting tank, putting pharmaceutical filtrated residue into the extracting tank, and carrying out second-time extraction so as to obtain a filtrate and distilled aromatic water; and mixing the two kinds of fine medicine liquid, carrying out filtration, and then, concentrating the filtrate to be 600L, thereby obtaining the Chinese herbal medicine disinfectant. According to the Chinese herbal medicine disinfectant, the purification ratio of removing cigarette smoke, PM2.5, formaldehyde and ammonia gas from air reaches 91-99.9%, and the in-air and direct killing rate to influenza viruses, Legionnella, streptococcus pneumoniae and staphylococcus albus reaches 84-99.9%, so that the Chinese herbal medicine disinfectant has outstanding advantages.