Peter Grayson Washington (August 31, 1798 – February 10, 1872) was an American official who served as U.S. Assistant Secretary of the Treasury.

[3] His maternal grandparents were Mary Elizabeth (née Wagener) Grayson and the Rev.

Senator William Grayson (through their mother, they were cousins of James Monroe).

[5] Washington began his career as a clerk in the United States Treasury.

[6] He was later promoted to Chief Clerk of the Treasurer's Office, Chief Clerk of Sixth Auditor; First Assistant Postmaster General, and Assistant Secretary of the Treasury under Secretary James Guthrie and Howell Cobb under Presidents Franklin Pierce and James Buchanan.