Brendan O'Carroll (born 15 September 1955) is an Irish writer, producer, comedian, actor and director. A popular comedian in Ireland since the early 1990s, O'Carroll is best known internationally for portraying the foul-mouthed Irish matriarch Agnes Brown in Mrs. Brown's Boys.

O'Carroll was born in Finglas West, a suburb of north Dublin. His mother, Maureen, was a Labour Party TD and his father Gerard O’Carroll a carpenter and he says this has had a huge impact on his life. He left school aged 12 and had a string of occupations including waiter, milkman, DJ, before making the move to comedy. Much of his comedy is about his childhood in Finglas and Dublin City.

O'Carroll has written seven novels, including The Mammy, The Chisellers, The Granny, The Scrapper (originally published as Sparrows Trap) and The Young Wan; a number of these have been translated into 12 languages and have been best sellers worldwide.

In 2014, O'Carroll will star once again as Agnes Brown in the film Mrs Brown's Boys D'Movie (working title).