The pop star will sing a number of well-known hits as he performs from Heywood’s Beach on 16 March.
Hosting the ceremony, which will be broadcast live and conducted both onboard Arvia and from the beach, will be DJs Sara Cox and Trevor Nelson.
P&O Cruises president Paul Ludlow said: "For our guests watching Arvia’s naming ceremony from home and from Barbados, this is a real treat.
"Olly, Sara and Trevor really do make a star-studded line-up, which showcases the contemporary entertainment for which P&O Cruises is known."
Nelson will take centre stage in Arvia’s Skydome and will introduce the bottle-smash moment with Arvia’s yet-to-be-revealed godmother, while Cox will host guests on one of Barbados’s beaches.
The pair will then sail on Arvia’s 11 March departure and will host late-night DJ sets onboard.