The role of angiogenesis in haematological malignancies has been recently recognized. In these tumors, angiogenesis has been investigated predominantly in the bone marrow (BM) compartment where it appears to be regulated by multiple interactions between malignant cells and different cell populations present in the tumor microenvironment. Thus, angiogenesis represents a therapeutic target that opens new perspectives for the treatment of haematological malignancies. Cytokines are small proteins that mediate intercellular communications, thus regulating important cellular functions, such as immune responses and angiogenesis. Some cytokines show anti-angiogenic properties through different mechanisms; these cytokines can interfere directly with biological functions of endothelial cells and/or target tumor cells inhibiting their capability to stimulate formation of new microvessels that are essential for tumor growth and dissemination. In this review we will summarize the current knowledge about the role of cytokines as anti-angiogenic agents in cancer, focusing our attention on the anti-angiogenic activity of IL-12 family members in haematological malignancies.