Summary: Lyme borreliosis is the most common tick-borne infectious disease in Europe and Poland. Human infection with B. burgdorferi causes skin lesions, acute systemic disease and, in some untreated patients, central nervous system or joint involvement. The invasion of B. burgdorferi spirochetes is accompanied by autoimmunity, which is responsible for multi-system symptoms. The diagnosis of Lyme disease is based on history, clinical symptoms and laboratory tests, mainly serological. In addition to the pathognomonic erythema migrans, paralysis of the facial nerve is characteristic of neuroborreliosis, and recurrent asymmetric involvement of the large joints, particularly the knees, is characteristic of the articular form. Late onset Lyme disease is difficult to diagnose because of non-specific symptoms that mimic autoimmune diseases. Lyme disease is sometimes over-diagnosed, unnecessarily treated, often sensationalized and suggestively described, while under-reported, and the number of actual cases may be 10 times greater than the number of reported cases. Currently, almost all patients with Lyme disease can be cured with antibiotics. However, some people continue to have symptoms (post-Lyme disease syndrome) after treatment that do not respond to antibiotic therapy. The problem remains the correct diagnosis, qualification for treatment and interpretation of the lack of clinical response to antibiotics. This article analyses the incidence, clinical features and treatment of Lyme borreliosis.