Samples of stored products were collected every month in 2012 in northern Anhui Province. Acaroid mites were isolated, identified and counted. Among 1 440 samples, 692(48.1%) had mite infestation and 34 species were identified, and the density was 32.1 mites/g. The species richness index (R(margalef)) ranged from 0.48 to 3.30, which was highest in August. The species diversity index (H') was 1.29-3.32, highest in July. The species evenness index (J) ranged from 0.91 to 0.97, highest in March. The number of species, breeding density, species richness index and species diversity index were stable in the year, while the species evenness index showed irregular change. There were many species of acaroid mites in the storage circumstance. The composition of acaroid mites were diverse, and changed with the seasons.