United States Ambassador to the Holy See

Ambassador of the United States to the Holy See Apostolicae Sedis Legatus Civitatum Foederatarum
Seal of the United States Department of State
Incumbent Louis L. Bono as Chargé d’Affaires-ai
Nominator	The President of the United States
Inaugural holder	William A. Wilson as Ambassador Extraordinary and Plenipotentiary
Formation	April 9, 1984
Website	U.S. Embassy - Vatican City

The Ambassador of the United States to the Holy See is the official representative of the United States of America to the Holy See, the leadership of the Roman Catholic Church. The official representation began with the formal opening of diplomatic relations with the Holy See by President Ronald Reagan and Pope John Paul II in 1984.

Before the establishment of formal diplomatic relations, President Franklin D. Roosevelt's Postmaster General James Farley was the first high-ranking government official to normalize relations with the Holy See in 1933. In addition, Myron Taylor would serve during World War II as an emissary for President Franklin D. Roosevelt. In 1951, President Harry S. Truman's pick of World War II hero Mark W. Clark was defeated.

Between 1951 and 1968, the United States had no official representative accredited to the Holy See. President Richard Nixon changed this when he appointed Henry Cabot Lodge, Jr. as his personal representative. President Jimmy Carter followed with the appointment of former New York City mayor Robert F. Wagner, Jr. Every ambassador to date has been a Roman Catholic. The most recent Ambassador was Ken Hackett. The post is currently vacant, with Louis Bono serving as Chargé d’Affaires. President Trump is yet to pick a full time Ambassador.