| Post: | Ambassador |
| Body: | the United States to Timor-Leste |
| Insignia: | US Department of State official seal.svg |
| Insigniasize: | 120 |
| Insigniacaption: | Seal of the United States Department of State |
| Incumbent: | Donna Ann Welton |
| Incumbentsince: | July 16, 2024 |
| Nominator: | The President of the United States |
| Appointer: | The President |
| Appointer Qualified: | with Senate advice and consent |
| Inaugural: | Shari Villarosa as Chargé d'Affaires ad interim |
| Formation: | May 20, 2002 |
| Website: | U.S. Embassy - Dili |
The diplomatic post of United States Ambassador to East Timor (now Timor-Leste) was created after the formalization of the independence of Timor-Leste from Indonesia on May 20, 2002. The United States recognized the new nation immediately, and an embassy was opened in Dili.
| Shari Villarosa – Career FSO | Chargé d'Affaires ad interim | May 20, 2002 | December 10, 2002 | |||
| Ambassador Extraordinary and Plenipotentiary | November 15, 2002 | December 10, 2002 | September 29, 2006 | |||
| W. Gary Gray – Career FSO | Chargé d'Affaires ad interim | September 30, 2006 | Unknown | July 4, 2007 | ||
| Hans G. Klemm – Career FSO | Ambassador Extraordinary and Plenipotentiary | May 30, 2007 | July 4, 2007 | February 20, 2010 | ||
| Judith Fergin – Career FSO | August 9, 2010 | September 16, 2010 | September 20, 2013 | |||
| Karen Clark Stanton – Career FSO[1] | November 18, 2014 | January 16, 2015 | December 22, 2017 | |||
| Kathleen M. Fitzpatrick – Career FSO | November 21, 2017 | January 19, 2018 | November 18, 2020 | |||
| C. Kevin Blackstone – Career FSO | January 6, 2021 | March 19, 2021[2] | August 2, 2021 | |||
| Thomas Daley – Career FSO | Chargé d'Affaires ad interim | August 2, 2021 | August 12, 2023[3] | |||
| Marc Weinstock | Chargé d'Affaires ad interim | August 15, 2023[4] | July 1, 2024 | |||
| Donna Ann Welton – Career FSO | Ambassador Extraordinary and Plenipotentiary | May 7, 2024 | July 16, 2024 | Incumbent |