The radon exhalation rates have been measured regularly in/around closed uranium mine sites in Japan based on the closed can method with scintillation cells. The measurement results of radon exhalation rate had a large fluctuation depending on the measurement points, and the averages of radon exhalation rates in the sites were approximately from 0.1 to 1 Bq m(-2) s(-1), while those at controls were around 0.02 Bq m(-2) s(-1). (c) 2004 Elsevier B.V All rights reserved.