Eleven genome types of adenovirus serotype 11 (Ad11) were identified among 20 strains isolated from healthy pregnant women and patients with urinary tract infections, respiratory tract infections, or pharyngoconjunctival fever by use of 13 restriction endonucleases: BamHI, BclI, BglI, BglII, BstEII, EcoRI, HindIII, HpaI, PstI, SalI, SmaI, XbaI, and XhoI. All genome types could be grouped into three genomic clusters according to their genetic homology expressed as pairwise comigrating restriction fragments. The genome types within a genomic cluster were very closely related. They shared on an average pairwise comigrating restriction fragments of 91.6-97.7%. The Ad11 strains of genomic clusters 1 and 3 were isolated from urine, whereas all the Ad11 strains isolated from the respiratory tract were identified as members of the genomic cluster 2. One genome type of Ad34 and one genome type of Ad35 were identified from a hemorrhagic cystitis patient and an organ transplant recipient, respectively. Both were closely related to Ad11. The genome type of Ad35 could be located in the Ad11 genomic cluster 1.