Postmortem examination of a captive-bred American kestrel (Falco sparverius) showed numerous white necrotic foci 1-2 mm in diameter throughout the liver and spleen. The results of light and electron microscopic studies and experimental transmission to a captive American kestrel and a barred owl (Strix varia) suggests a herpesvirus similar to those dsecribed for owls and other falcons in the U.S. This is the first report of a naturally occurring case of inclusion body disease of falcons in the American kestrel.