Abstract: DNA methylation, one important form of epigenetic modifications, plays an important role in gene regulation in animals. With more attentions paid to DNA methylation in insects in recent years, it was found that besides certain similarities between insects and mammals, there are also some unique features and functions in DNA methylation of insects. Here, we reviewed the advances in researches on DNA methylation in insects and focused on its main characteristics and functions so as to provide some references for further exploring DNA methylation in insects. The type and nature of DNA methyl-transferase vary widely across insect species, and the DNA methylation mainly occurs in gene areas in insects and the level is low. The functions of DNA methylation in insects mainly involve the regulation of embryonic development, participation in genomic imprinting, regulation of caste and wing differentiation, sex determination, and involvement in pesticide resistance.

Key words:  Insects, DNA methylation, epigenetics, caste differentiation, wing differentiation, pesticide resistance