Abstract: Transdermal drug delivery system (TDDS), as a percutaneous drug administration route, has received extensive attention in recent years. However, the existence of stratum corneum (SC), the main skin barrier, greatly limits the effects of most drugs. Microneedles(MNs) can penetrate the SC and create transient microchannels for drug percutaneous permeation, and subsequently deliver drugs to the dermis or subcutaneous layer. Meanwhile, administration of MNs is minimally invasive and easy to operate, with no pain and good control of drug release, so it has a broad application prospect for topical or systemic skin disease. The present paper mainly reviews the preparation and classification of MNs, and the latest progress of MNs in treating skin tumors, with further discussion about the development prospect of MNs in the field of biomedical research, which will provide reference for clinical application of MNs transdermal delivery system.