The Deputy Secretary of the Treasury, in the United States government, advises and assists the Secretary of the Treasury in the supervision and direction of the Department of the Treasury and its activities, and succeeds the Secretary in his absence, sickness, or unavailability. The Deputy Secretary plays a primary role in the formulation and execution of Treasury policies and programs in all aspects of the Department's activities.

In addition, the Deputy Secretary is the only official other than the Secretary than can sign a Treasury Order, which is a document that delegates authority residing in the Secretary or Deputy Secretary to another Treasury official, establishes Treasury policy, and establishes the reporting relationships and supervision of officials.Former Deputy Secretaries include Roger Altman, Lawrence Summers, Stuart E. Eizenstat, Kenneth W. Dam, and Samuel W. Bodman.

The office of Deputy Secretary is the successor of the "Under Secretary of the Treasury", the former chief deputy to the Secretary. Today, several officials hold the title of "Under Secretary" of the Treasury. Among those who served as Under Secretary when it was the number-two position in the department include Dean Acheson, Henry Morgenthau, Jr., and O. Max Gardner (1946–47).

Neal S. Wolin was announced as President Obama's nominee for Deputy Secretary on March 23, 2009.

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