Thrombocytopenia is a common complication of HIV infection. The low platelet count can be caused by multiple mechanisms including immune-mediated destruction, decreased platelet production, effects of drugs on progenitors, or by the development of a form of thrombotic thrombocytopenic purpura (TTP). Bleeding problems associated with the thrombocytopenia can be accentuated by the presence of platelet dysfunction produced by drugs used to treat HIV/AIDs or its complications. Therapy should be directed at reducing the load of the HIV virus of the patient supplemented by other therapies chosen depending on the specific underlying cause.