A higher incidence of cancer has been observed in Human Immunodeficiency Virus (HIV) infected individuals as compared with healthy people of the same age. A complex relationship between HIV-induced immune suppression, chronic antigenic stimulation, and oncogenic virus co-infections may promote carcinogenesis and increase the risk of developing tumors in these patients. Cancers in HIV subjects include the AIDS-defining malignancies (ADMs) and other non-AIDS-defining malignancies (NADMs). Antiretroviral therapy has reduced the incidence of ADMs whereas a concurrent increase of NADMs was observed in the last years. Biomarkers are measurable parameters, characterizing normal or pathogenic processes, which could provide a high potential for risk evaluation and diagnosis of patients. Therefore, the early detection of cancer biomarkers in HIV-positive subjects would be useful to identify patients at most risk of tumor disease development. This review will focus principally on the risk assessment and diagnostic role of several biomarkers of malignancy in HIV patients including cellular and viral biomarkers, cytokines, immune activation molecules and genetic polymorphisms.