Plasmacytoid dendritic cells (pDCs) as innate immune cells can produce a large amount of interferon-alpha (IFN-α). During the stage of acute human immunodeficiency virus (HIV) infection, pDCs can inhibit HIV replication by releasing IFN-α and activating adaptive immune responses. In the stage of chronic HIV infection, pDCs play a role in immune suppression by regulating immunocytes and damage of the immune system by depletion of the lymphocytes. Finally, pDCs have influence on the disease progression of acquired immune deficiency syndrome (AIDS).