Introduction: Ticks are parasites, arthropods from the family of mites. They are important as vectors of some infectious diseases. In Croatia, most often occur Tick encephalitis and Lyme boreliosis, a highly tularemia, Q fever ehrlichiosis, babesiosis and some Rickettsial. The diseases occur in certain areas of country so we are talking about "natural foci". Infected Ticks with encephalitis are usually in northern and northwestern Croatian territory, between the Sava and Drava river. Infected ticks with the bacteria that cause Lyme boreliosis are in the whole area of Gorski Kotar. Goals: The aim of this research is to show and to determine the distribution of tick-borne meningitis (TBE) and Lyme boreliosis (LB) in the Primorje-Gorski Kotar County, particularly in the area of Gorski Kotar and the coast, and then compare with the rest of Croatia, Europe and rest of the world. Subject and Methods: Collected data were obtained at the Department of Public Health Kvarner County in Rijeka and the Health Center in Delnice for period between 2008 and 2015. After examination of the medical records, it is accessed the prospective study and the results are obtained from them. Results: We analyzed the distribution of patients by age, sex, occupation, time of illness, site of disease and the interest of patients. Statistical analyses of the resulting data are presented graphically and numerically. In this work are researched number of applications disease, deaths from infectious diseases for the period between 2008 and 2015. The largest number of patients were old, retired people in the area of Delnica and Kupjak. The lethality does not exceed 1%. In recent years it was 0,2%. Conclusion: From the results it is concluded that the morbidity and mortality of tick-borne encephalitis and Lyme boreliosis after being bitten by a tick in the Primorje-goranska are low and without greater meaning, but in the “natural foci” may be significant.