Biologics, including proteins, peptides, and nucleic acids, represent a promising class of therapeutics for dermatological diseases. However, their large molecular size and instability limit their delivery via conventional topical routes. Microneedle (MN) technology offers a minimally invasive solution by creating transient microchannels in the skin, enabling efficient intradermal delivery of biologics. This review explores the design, mechanisms, and clinical applications of MN-assisted delivery systems for biologics, with a focus on their use in treating psoriasis, skin cancer, and vaccine delivery.