Cytokines are extracellular signalling molecules involved in cell to cell communication. They can be synthesized by many cell types and have multiple actions on cells from the hematopoietic or other lineages. The putative role of these molecules as autocrine or paracrine growth factors for tumor cells as well as their capacity to stimulate immune functions has encouraged their study in brain and other cancers. Brain tumor cells are capable of secreting some cytokines and brain tumor tissue shows expression of certain cytokine receptors, compatible with a function of these molecules in brain tumor genesis or malignant progression. Here, we critically summarize these findings and discuss their implication for brain tumor therapy.