Editors' Summary: The public trust doctrine has been the subject of a large and growing body of scholarly analysis. This amorphous legal doctrine, which varies from state to state, generally provides that states hold certain submerged land and tidelands in trust for their citizens. The public trust literature has thoroughly discussed the use of the doctrine in the management of coastal areas. One issue that has not been addressed in detail is the potential preemption of state public trust doctrines in federal property. This Article examines the federal government's capability to preempt state public trust doctrines under the federal property power. The author observes that the resolution of the preemption issue turns on the type of federal property involved. She concludes that state doctrines that conflict with the purpose of special use federal property, such as national parks and wildlife refuges, may be preempted. However, preemption will only occur after a site-specific determination that a particular state public trust doctrine conflicts with a federal property purpose.