Francis Hagai (c. 1940 – 7 July 1974) was the leader of the Hahalis Welfare Society (HWS) on Buka Island, in what is now the Autonomous Region of Bougainville in Papua New Guinea. He received a Catholic education but later sought to establish an alternative church and revive traditional customs. In 1962 he led the HWS in a conflict with Australian authorities over a tax dispute and was briefly jailed. Although he was unsuccessful in bids for public office, he has been credited with drawing greater attention to Buka.