Activation of immune cells to mediate an immune response is often triggered by potential 'danger' or 'stress' stimuli that the organism receives. Within the mitogen-activated protein kinases (MAPKs) family, the stress-activated protein kinase (SAPK) group was defined as group of kinases that activated by stimuli that cause cell stress. In the immune cells, SAPKs are activated by antigen receptors (B- or T-cell receptors), Toll-like receptors, cytokine receptors, and physical-chemical changes in the environment among other stimuli. The SAPKs are established to be important mediators of intracellular signaling during adaptive and innate immune responses. Here we summarize what is currently known about the role of two sub-groups of SAPKs - c-Jun NH(2)-terminal kinase and p38 MAPK-in the function of specific components of the immune system and the overall contribution to the immune response.