Cytokines are a heterogeneous group of peptides that play an important role in intercellular communication, regulation of innate and specific immunity, hematopoiesis, interaction between the immune system and neuroendocrine network as well as in reproduction and development. Seminal plasma provides an immunological environ- ment for the semen and contains important biological response mediators. Numerous studies investigated the presence of various cytokines in the seminal plasma and tried to correlate cytokine levels with sperm quality and male fertility. However, the patho- physiological significance of seminal cytokines in sperm function is still not completely understood. The purpose of this review is to provide a brief summary of the extensive literature dealing with cytokines in the seminal plasma and to discuss the contribution of local cytokine immunity to male fertility. Cytokines are a heterogeneous group of peptides that play an important role in intercellular communication, regulation of innate and specific immunity, hematopoiesis, interaction between the immune system and neuroendocrine network as well as in reproduction and development. Seminal plasma provides an immunological environ ment for the semen and contains important biological response mediators. Numerous studies investigated the presence of various cytokines in the seminal plasma and tried to correlate cytokine levels with sperm quality and male fertility. However, the patho- physiological significance of seminal cytokines in sperm function is still not completely understood. The purpose of this review is to provide a brief summary of the extensive literature dealing with cytokines in the seminal plasma and to discuss the contribution of local cytokine immunity to male fertility.