Olivia-Mai Barrett is an English actress from London, United Kingdom. She began her career in music videos and the Disney series Penny on M.A.R.S., in which she played the lead role, as well as in the series Alex & Co. on Disney Channel.

In 2019 she was the only actress in the last of the eight episodes of the BBC miniseries Soon Gone: A Windrush Chronicle, a series showing life in Britain for successive generations of people of Caribbean origin, in the role of Michaela Williams. In The Observer, Kwame Kwei-Armah was quoted: "Her performance was incredible, I was struck by how she brought so much empathy and insight to the role." Barrett shares the same background as her character in the series, as her father is mixed race and her grandfather is Jamaican; the Windrush story is part of her family history.

In 2020 she starred in the film My Dad's Christmas Date.