Spencer Leniu (born 8 September 2000) is a Samoa international rugby league footballer who plays as a prop for the Sydney Roosters in the National Rugby League (NRL).

Of Samoan descent, Leniu was born in Auckland, New Zealand, and grew up in Western Sydney. He played for the Minchinbury Jets in the Penrith District Junior Rugby League.

Leniu made his first grade debut for Penrith against the Cronulla-Sutherland Sharks in round 21 of the 2019 NRL season which ended in a 26–20 victory for Penrith at Panthers Stadium.

Leniu played 12 games for Penrith in the 2020 NRL season but did not feature in the clubs finals campaign or the 2020 NRL Grand Final loss to Melbourne.^{[citation needed]}

Leniu played a total of 19 games for Penrith in the 2021 NRL season including the club's 2021 NRL Grand Final victory over South Sydney.

Leniu played 25 games for Penrith in the 2022 NRL season including the clubs 2022 NRL Grand Final victory over Parramatta.

In October Leniu was named in the Samoa squad for the 2021 Rugby League World Cup.

On 18 February, Leniu played in Penrith's 13–12 upset loss to St Helens RFC in the 2023 World Club Challenge. On February, Leniu announced he will join Sydney Roosters from 2024 onwards. Leniu was selected as 19th man in the NSW Blues State of Origin squad for Game 3. Leniu played 21 games for Penrith in the 2023 NRL season including the clubs 26–24 victory over Brisbane in the 2023 NRL Grand Final as Penrith won their third straight premiership.