The aim of the study was to detect bacteria pathogenic to humans, such as Borrelia burgdorferi sensu lato, Rickettsia spp, and Coxiella burnetii in ticks found in municipal parks in Warsaw, including The Royal Łazienki Park, Mokotów Fields, Józef Sowiński Park, Ujazdów Park and Fort Bema Park. To detect microorganisms PCR technique was used. It was shown that 6.1% of the ticks in Warsaw's parks are infected with B. burgdorferi sensu lato, and 2.9% with Rickettsia spp. Analysis of sequencing results revealed in examined ticks the presence of B. burgdorferi sensu stricto and R. helvetica.