Mycoplasma pneumoniae (Mycoplasma pn.) is a common airway pathogen in childhood. Mycoplasma pn. infections appear as epidemics (every 3-7 years) and are very often the cause of community--acquired pneumonia among people being in close contact for longer period of time and specially in children, young adults and elderly. For many years, routine diagnosis of Mycoplasma infections based upon ELISA methods, which determine a level of specific Mycoplasma antibodies in class G, M, A in serum. One of the most reliable new diagnostic technique is PCR, which determines Mycoplasma pn. DNA in clinical samples. The aim of the present study was to compare PCR and ELISA techniques in the diagnosis of Mycoplasma pn. airway infections in children. Sixty two children aged 2-17 years, with symptoms of Mycoplasma pn., infection, with presence of IgM, or/and IgG against Mycoplasma pn. in serum took part in the study. All children had antibodies against Mycoplasma pn. measured by ELISA method and Mycoplasma pn. DNA in PCR. The results showed high similarity between both methods (ELISA and PCR) in samples from swab throat.