The vote is to elect 100 lawmakers who will then pick a parliament speaker, a president and a prime minister for Iraqi Kurdistan, which gained self-rule in 1991, Reuters reports.
The parliamentary elections, originally supposed to be held in 2022, have been repeatedly delayed due to disagreements between the two dominant parties, the Kurdistan Democratic Party and the Patriotic Union of Kurdistan.
With opposition parties weak, the two parties are likely to extend more than three decades of power-sharing.
Polls close at 6 p.m. (1500 GMT).
"We hope that a unified regional government will be formed as soon as possible and that the situation of citizens will move for the better," said Nechirvan Barzani, president of Iraqi Kurdistan, after casting his vote in Kurdish capital Erbil.
MNA/