The invention discloses an acetaldehyde absorber based on asbestos modification and a preparation method thereof. The preparation method comprises the steps that 1, folium ginkgo, herbal artemisiae scopariae, fructus evodiae, honeysuckle stems, rhizoma phragmitis and water are mixed and decocted, filtrate is taken after filtering is performed, and a Chinese herb extracting solution is prepared; 2, asbestos, carbon nano tubes, nano-palladium and nano-silver oxide are soaked in the Chinese herb extracting solution, and then a filter cake is taken after filtering is performed; 3, the filter cake is dried and ball-milled, and the acetaldehyde absorber based on asbestos modification is prepared. The acetaldehyde absorber based on asbestos modification has excellent acetaldehyde absorption ability, and meanwhile the preparation method is easy to operate and convenient to popularize.