Babesiosis is an emerging parasitic, anthropo-zoonotic tick-borne disease, seldom diagnosed in humans. Caused by Protozoa, Babesia (also called Piroplasma) intraerytrocytic piriform microorganism. Infection of vertebrates is transmitted by ticks. Out of more than 100 Babesia species/genotypes described so far, only some were diagnosed in infected humans, mostly B. microti, B. divergens and B. venatorum (Babesia sp. EU1). Infection in humans is often asymptomatic or mild but is of a particular risk for asplenic individuals, those with congenital or acquired immunodeficiencies, and elderly. Infections transmitted with blood and blood products raise concerns in hemotherapy. Epidemiological situation of babesiosis varies around the world. In Europe, no increase in the number of cases was reported, but in the USA its prevalence is increasing and extension of endemic areas is observed. The aim of this publication is to describe the problems connected with the current epidemiological situation, diagnosis and treatment of human babesiosis with regard to clinical status of patients.