Joseph James Cella (/ˈsɛlə/ SELL-əh; born November 14, 1969) is an American diplomat and political advisor, who served concurrently as the United States Ambassador to Fiji, Kiribati, Nauru, Tonga, and Tuvalu from 2019 to 2021.

[6] Cella was presented his credentials to be the 16th United States Ambassador to Fiji and its surrounding islands of Kiribati, Nauru, Tonga, and Tuvalu on December 23, 2019, by Fijian President Jioji Konrote.

[9] On January 30 of next year, Cella met with Joseph Lengyel, then a member of the Joint Chiefs of Staff, to "emphasize the importance of Fiji’s State Partnership Program with the Nevada National Guard".

[11] During the COVID-19 pandemic, Cella received an additional $27.7 million and relief supplies for his ambassadorial countries from the United States Agency for International Development (USAID).

[15] In May 2020, Cella's Embassy requested grant proposals to try to "support economic resilience" in Fiji, Kiribati, Nauru, Tonga, and Tuvalu at the "grassroots level" during the COVID-19 pandemic.

[3][19][20] In 2004, he founded the National Catholic Prayer Breakfast along with Rick Santorum, and Leonard Leo, which they created in response to Pope John Paul II's call for a new evangelization.

[20] It has featured many notable guest speakers like George W. Bush, John Roberts, Paul Ryan, Raymond Leo Burke, Samuel Alito, and Antonin Scalia.