Abstract： Dendritic cells (DCs), a subset of professional antigen-presenting cells, are classified into different subtypes. DCs can initiate and regulate immune responses after receiving signals from microbes and extracellular environment. They express different microbial receptors, cytokine receptors and surface molecules. The functional status of DCs determines whether they trigger immune response or induce immunotolerance. Hence, DCs with abnormal function can result in different skin diseases, including autoimmune diseases and cancers. Conversely, DCs can also be exploited for the development of vaccines to treat these diseases.