The retrospective study was performed (2011-2013) on a group of 34 patients admitted to Toma Ciorba Infectiou Diseases Hospital in Chisinau. It is based on the data analysis of patient observation charts. Purpose: Evaluation epidemiological, clinical and paraclinical features of borreliosis. The parameters used in this study were: general patient data, complaints at admission, history of current disease, treatment prior to hospitalization, anamnesis data, clinical data paraclinical data, hospitalization period, disease progression data, treatment effectiveness data. Retrograde – current literature data were studied; analytical - obtained data were analyzed and conclusions were drawn; mathematical - calculations for the schematic representation of research results were performed; statistical - literature study of the epidemiological situation of borreliosis in the Republic of Moldova was carried out. The mean age was 38.4 years, ranging between 10 and 71 years. Of them, there were 18 men and 16 women; 2 patients from rural areas, 32 patients from urban areas. In 2011 there were 15 patients, 2012 – 8 patients, 2013 – 11 patients. Among the total number of patients, 33 patients were diagnosed and treated at stage I of disease and only 1 patient at stage II, and there was no patient at stage III. Clinical symptomatology included: migratory erythema - 26 cases, pain in the bite area – 11 cases, skin pruritus – 1 case, fever -16 cases, chills – 5 cases, arthralgia – 16 cases, myalgia – 4 cases, headache – 12 cases, physical asthenia – 27 cases, localized adenopathies – 4 cases. The patient with stage II of disease had fever 380C for 3-4 months, general asthenia and arthralgia. The definitive diagnosis of Lyme disease was performed by determining IgM and IgG anti-borrelia antibodies (ELISA). In 29 cases, IgM was positive, while IgM + IgG in 5 cases. The treatment regimens were consisted of one or two antibiotics (doxycycline and / or penicillins and / or cephalosporins), ketoconazole, novocaine, vitamins, cetirizine, calcium gluconate infusions, and desensitisers. The majority of cases occur in May - October (the maximum index reaching 34.8% in August), which corresponds to the period of intense of recreational areas by the population and contact with causal agent vector. Lyme disease can occur atany age, both male and female being equally concerned. The evolution of Lyme disease is favorable and has good prognosisif prompt and correct treatment is performed.