Human Bocavirus (HboV) was recently cloned by a systematic screening of nasopharyngeal samples from children hospitalized for respiratory tract infections. This virus, genus Bocavirus, family Parvoviridae, was identified by screening for its DNA in 5% of nasopharyngeal aspirates, as reported in several studies. It may be responsible for upper and lower respiratory tract infections of young children under five years with a peak rate in winter. Because of a high rate of viral co-infections, its pathogenic role in these infections should be documented. Further studies are required to determine the role of this possibly systemic virus in other affections.