Josaia is a given name. Notable people with the name include:

Josaia Raisuqe (1994–2025), Fijian rugby union footballer Josaia Rayawa, Fijian chief, religious leader, and politician Josaia Tavaiqia (1931–1997), Fijian chief and politician Josaia Waqabaca, Fijian politician

See also Josiah (given name)