Approximately 20,000 stool specimens from patients with diarrhea visiting 1 urban and 1 rural hospital in Bangladesh during January 2001-May 2006 were tested for group A rotavirus antigen, and 4,712 (24.0%) were positive. G and P genotyping was performed on a subset of 10% of the positive samples (n = 471). During the 2001-2005 rotavirus seasons, G1P (36.4%) and G9P (27.7%) were the dominant strains, but G2 and G12P were present in 15.4% and 3.1% of the rotavirus-positive patients, respectively. During the 2005-06 rotavirus season, G2P (43.2%) appeared as the most prevalent strain, and G12P became a more prevalent strain (11.1%) during this season. Because recently licensed rotavirus vaccines include only the P specificity, it is unknown how the vaccines will perform in settings where non-P types are prevalent.