Hundreds of Canada's regional chiefs are in Winnipeg for the election.
Voting began at 9 a.m. CT and results of the first ballot should be available by 1 p.m.
The results announcement will be streamed live online by CBC.
So far, 406 chiefs or proxies have registered to vote. A total of 639 votes can be cast.
The AFN's top job has been vacant since the abrupt resignation in May of Shawn Atleo amid controversy over his support of the federal government's proposed overhaul of aboriginal education.
Three people are in the running for the job:- Perry Bellegarde, chief of the Federation of Saskatchewan Indian Nations. The former regional vice-chief for the AFN ran against Atleo in the 2009 AFN leadership election. It was a 23-hour voting contest that ended on the eighth ballot, after six successive ballots in which Bellegarde and Atleo were virtually tied.
- Leon Jourdaine, chief of the Lac La Croix First Nation in northwestern Ontario.
- Ghislain Picard, regional chief for Quebec and Labrador, who has been interim national chief since Atleo's resignation.
The winning candidate needs support from 60 per cent of the registered voters.