Human astrovirus (HAstV) is the second most common causes for viral gastroenteritis in young children.This study was undertaken to investigate the molecular epidemiology and the genomic characterization of astrovirus infection in infants in Wuhan, China.Between June 2004 and May 2005, the fecal specimens of 335 infants (under the age of 3 years) were collected from the outpatient department of Wuhan Childrens Hospital, and 33 specimens were found to be positive for HAstV RNA using RT-PCR with the primer pairs (Mon340/348).Further sequence analysis with the primer pairs (Mon269/270), 23 samples were found to be astrovirus genotype 1 and mostly (21/23) of them had highest identity (>98%) to Mongolian strain, while only one sample (WH1859) was identified as genotype 3.We also cloned and sequenced the complete ORF2 of this HAstV-3 strain isolated from fecal sample, which has <95% (92.4~93.5%) nucleotide identity and >0.05 (0.063~0.075) distance by phylogenetie analysis to the reference HAstV-3 stains in Genbank, so we believe that WH1859 represents a new distinct subtype within HAstV-3 strains.Our study clearly indicate that astrovirus as an etiological agent has a significant role in infant gastroenteritis in Wuhan city, further study are needed to understand the nature of astrovirus infection and to provide strategies for the prevention and control of astrovirus infection in children in China.