We typed 18 isolates of Legionella bozemanii obtained from clinical and environmental sources by pulsed-field gel electrophoresis. Each of the unrelated strains showed individual restriction patterns of the genomic DNA when either the SfiI or NotI restriction enzyme was used. One strain isolated from a patient with nosocomial legionellosis and two strains from the corresponding hospital water supply were indistinguishable, arguing for a transmission of L. bozemanii from the water supply to the patient. In conclusion, macrorestriction analysis is a valuable tool for studies of the molecular epidemiology of L. bozemanii.