Fanitesi Niu (born 11 August 2001) is a Tonga international rugby league footballer who plays as a centre or winger for the Leigh Leopards in the Super League.

He previously played for the Dolphins and the Brisbane Broncos in the NRL.

Niu was born on 11 August 2001 in Brisbane, Queensland, Australia. He was educated at Marsden State High School and played his junior rugby league for the Forest Lake Magpies. He is a first cousin of David Fifita.

Niu also represented the 2018 Australian Schoolboys.

Niu represented Tonga in 2019 Great Britain Lions tour making his international debut. He then played for Tonga 9s in the 2019 Rugby League World Cup 9s.

On 4 June 2020, Niu made his NRL debut for the Brisbane Broncos, coming off the interchange bench in a record 59–0 home defeat against the Sydney Roosters. On 27 June 2020, he made his starting debut at fullback against the Gold Coast Titans.

Niu made a total of six appearances for Brisbane in the 2020 NRL season after suffering a season-ending wrist injury in round 10, as the club finished last on the table and claimed its first-ever wooden spoon.

In round 16 of the 2021 NRL season, Niu scored two tries in a 26–18 victory over Cronulla-Sutherland.