The Hepatitis B virus (HBV) reactivation is defined as proliferation of HBV and hepatitis flare after medication of anti-cancer drugs and/or immunosuppressant drugs in inactive HBV carriers or patients with past illness by HBV infection. In January 2009, the guideline for prevention of immunosuppressive or chemotherapy-induced reactivation of HBV infection was established by Japanese study groups of the Ministry of Health, Labour and Welfare. We then surveyed and analyzed order numbers of the tests of HBV DNA and anti-HBc, the rate of positive results and the department of the doctors who ordered those tests, the patient ages and clinical profiles and the purpose of the tests, from 2008 to 2009 before and after announcement of the guideline. The total numbers of tests of HBV DNA were 942 in 2008 and 1350 in 2009, and those of anti-HBc were 430 in 2008 and 904 in 2009. The percentage of the orders for anti-HBc from doctors in department of gastroenterology and medicine was 71.4% in 2008 and decreased to 53.4% in 2009, instead those of hematology and oncology, pulmonary surgery and gynecology increased remarkably. The positive rates of anti-HBc increased among the patients over age 40, especially it was more than 40% over age 50. The number of the tests for the follow-up after immunosuppressive or chemotherapy increased over 4 folds. This report made clear the actual situation of screenings for the HBV reactivation by analyses of the bases in the orders and the results of the virus tests in our hospital.