Shadeau Brain (pron. "Shadow", born 13 February 2004) is an Australian rules footballer who currently plays for the Brisbane Lions in the Australian Football League (AFL).

Brain grew up in Noosa and attended Tewantin State School and Sunshine Beach State High School. He later moved to Finley, New South Wales, where his father was from, and attended Finley High School.

At the age of 16, Brain returned to the Sunshine Coast, where he joined the Noosa Tigers.

Brain made his debut in the Victorian Football League (VFL) for Brisbane's reserves team against Gold Coast in round 18 of the 2022 season. He played two more games against Richmond and Werribee.

He was formally drafted to Brisbane on 30 November 2022 in the 2023 rookie draft as a Category B rookie.

In 2023, Brain did not play any AFL games, however he continued to play in the VFL for Brisbane. In round 13 of the 2023 season, he kicked a career-best 4 goals against Sydney.

Brain made his AFL debut against Adelaide in round 9 of the 2024 season.

Brain has 12 siblings, including seven brothers who also play Australian rules football.