Francis Xavier Castellano (born January 7, 1964) is a United States Navy captain currently assigned as the commanding officer of Center for Surface Combat Systems.

Captain Castellano was listed as executive officer of USS Vella Gulf on May 5, 2014, during a Holocaust memorial ceremony in Haifa, Israel.

[4] Castellano was the commanding officer of Bainbridge during the April 12, 2009 rescue of Captain Richard Phillips from pirates off the coast of Somalia.

[10] Vice Admiral William E. Gortney reported the rescue began when Castellano determined that Phillips' life was in imminent danger and ordered the action.

The U.S. Navy evacuated Maersk Alabama's captain, Richard Phillips, to Bainbridge and then flew him by helicopter to USS Boxer for a medical evaluation.

At his parish of Our Lady of Mount Carmel Catholic Church in Patchogue, he served in turn as an altar boy, usher, lector, and Extraordinary Minister of Holy Communion.