The purposes of this cross sectional descriptive study were to determine the situation and associated factors of hepatitis B immunization for healthcare workers (HCWs) in Thai governmental hospitals. Self administered questionnaires were sent to 524 governmental hospitals through out the country during October and November 2004, and the response rate was 78.2 percent (410 out of 524 hospitals). Majority of the hospitals had the hepatitis B immunization policies for their healthcare workers 310/410, 75.6%). The implementations of preexposure program (253/410, 61.7%) were more frequent than postexposure program (238/410, 58.0%). The preplacement examinations of hepatitis B immune statuses were conduceted for all new HCWs in 127 hospitals (31.0%) and only for new high risk HCWs in 108 hospitals (26.3%). The preexposure immunizations for high risk HCWs were carried out in 156 hospitals (38.0%). Financial problem was the main obstacle for running the immunization program and vaccine provision by the government was the most needed support for the hospitals. Hospital Accreditation (HA) statuses of the hospitals were found to related to the existence of their hepatitis B immunization policy and immunization. Policy and implementation of hepatitis B immunization f9or HCWs, especially for the high risk ones, should exist in all government hospitals. Central authority should: (1) provide adequate budget of hepatitis B vaccine for the hospitals and ; (2) prepare and distribute the national standard guideline on hepatitis B immunization for HCWs. The reimbursement regulation for lhepatitis B vaccine should also be revised.