Pneumonia is an inflammation of the lung caused by microbial or viral infection. It is an important factor of morbidity for children in the developed world, as well as a frequent cause of death of children in the developing world. Chemokines are a very important part of the immune system. The purpose of this study was to investigate the role of polymorphisms of chemokine RANTES (-28C/G and-403G/A) in the development of pneumonia in children. The study included two groups of children, the patient group and the control group. The patient group consisted of 60 children, who were hospitalized with the diagnosis of pneumonia from November 2009 until May 2010. The control group consisted of 135 healthy children who had no previous history of lower respiratory tract infections. According to the results, polymorphism of chemokine RANTES -28C/G was associated to the development of pneumonia in the studied population. Polymorphism of chemokine RANTES -403G/A was not associated to the development of pneumonia in the same population. Serum levels of chemokine RANTES were lower in children who were carriers of the polymorphism -28C/G compared to children who had the normal gene type. Also, serum levels of chemokine RANTES were higher in children with pneumococcal pneumonia compared to children with pneumonia caused by other pathogens.