Lyme disease is a chronic, multiorgan disease caused by the spirochete Borrelia burgdorferi, which is transmitted by Ixodes ticks. Poland has medium to high rate of tick infection. Lyme disease incidence has been increasing in recent years, with the peak incidence recorded in the summer, especially in endemic areas. The risk of infection depends on the type of spirochete and the time it is present in the human skin. It is crucial to remove the parasite as soon as possible, not later than 24 hours after the spirochete enters the body. The infection usually occurs in three stages, although not all of them have to be present. A characteristic erythema migrans or, less common, lymphocytic lymphoma, may be observed in the first stage of the disease. General symptoms, such as myocarditis, arthritis or nervous system involvement, are developed in the second stage. In the late stage of the disease, serious irreversible complications of the nervous system, musculoskeletal system or the skin occur. The diagnosis of Lyme disease is based on a history of tick bite as well as on the presence of clinical symptoms confirmed by serological findings. The presence of erythema migrans is sufficient for diagnosis and treatment initiation, therefore laboratory diagnostics is not necessary in this case. Serological diagnostics is primarily based on ELISA testing, while the second step uses a Western blot test. Positive serology test in the absence of clinical symptoms or a positive medical history is insufficient for diagnosis and treatment initiation. The type of the antibiotic used as well as the route and duration of its administration depend on the stage of the disease and on the affected organ. The most common antimicrobials used in the treatment of Lyme disease include amoxicillin, doxycycline (over the age of 12 years) and ceftriaxone.