"As a senior player it is my responsibility to support the captain and everyone else in the team," Gayle said in a statement from Cricket West Indies.
"This will probably be the biggest World Cup, so there will be great expectations and I know we'll do very well for the people of the West Indies."
Wicketkeeper batsman Shai Hope, who has played 50 ODIs with five centuries to his name, was named the vice captain for the ongoing tri-series in Ireland, which also features Bangladesh.
West Indies, champions in 1975 and 1979, start their World Cup campaign on May 31 when they take on Pakistan in Nottingham.
(Reporting by Rohith Nair in Bengaluru; editing by Sudipto Ganguly)
