The Wandsworth-born star, who has appeared in Ted Lasso, Game of Thrones and Sex Education, will be at the naming ceremony in Barcelona on 23 April.
Earlier this year, Waddingham earned a Bafta TV Award nomination for her own Apple TV+ holiday special Hannah Waddingham: Home for Christmas.
In 2023, she co-hosted the Eurovision Song Contest in Liverpool alongside Alesha Dixon and Graham Norton.
Waddingham joins a star-studded group who have served as godparents to a Princess ship.
They include Diana, Princess of Wales (Royal Princess, 1984); Kate Middleton, Princess of Wales (Royal Princess, 2013); Audrey Hepburn (Star Princess, 1989); Sophia Loren (Crown Princess, 1990); and Martha Stewart (Crown Princess, 2006), among others.
Princess Cruises president John Padgett said: “We’re delighted to welcome the elegant Hannah Waddingham to serve as godmother for our sensational new Sun Princess.
“Just like Sun Princess, she exudes sophistication, beauty and wonderment through her inspiring work as a talented and award-winning actress and performer.
“We’re truly honoured Hannah will officially name our most impressive, luxurious and stunning ‘Love Boat’ ever created, and join an esteemed group of Princess Godparents including members of the royal family.”
The 4,300-guest ship, Sun Princess, entered service on 28 February after its launch was delayed twice to allow additional work to be completed.
It is currently sailing a series of Mediterranean voyages before debuting in Ft Lauderdale, Florida, in October for the ship’s first Caribbean season.
