The name of this disease, which is spread by ticks, comes from the town of Lyme in Connecticut, USA. The first cases of the disease where first recorded there in 1972. Initially, the disease was first recorded only in the US, where in 1994 as many as 13 thousands cases occurred. Nowadays, in some places in the US, the disease takes on epidemic proportions. In Poland, the research shows that the main concentrations of the cases are in Western Pomerania, the Mazurian Lake District and Białystok area. This coincides with the location of the main forest areas in Poland. The author describes the reservoir and the infection source, process of infecting animals and people and the symptoms in people.