Recently distribution of hepatitis B virus (HBV) genotypes (GT) in the patients with acute HBV infection has been changing. It has been suggested that acute hepatitis caused by GTA HBV becomes chronic more often than that by other genotypes. We studied HBsAg-positive period in 88 patients with various HBV genotypes. HBsAg-positive period in GTA HBV is longer than that in GTB and GTC. HBsAg-positive period exceeded 6 months in 3 of 47 patients with GTA HBV. One of the three patients became chronic. GTA HBV, which is detected more than half of the patients, is related to prolonged or chronic outcome. Universal HBV vaccination program for the prevention of HBV infection should be launched in the near future.