Kitty Wilmer O’Brien was an Irish painter. Born in India in 1910 to Irish parents, O’Brien grew up in Dublin, Ireland. She attended the Royal Hibernian Academy schools and later the Metropolitan School of Art in Dublin. Upon completing her studies, she was awarded a scholarship to continue her artistic education at the Slade School of Art in London. The artist first exhibited with the Royal Hibernian Academy in 1946, a practice which continued regularly for over thirty years.

O’Brien is perhaps best known for her distinctive landscape paintings which featured bold brushwork and an emphasis on movement in trees and skies. Her affection for the scenery of her native Ireland, particularly that of County Mayo, was apparent in numerous watercolour and oil paintings produced throughout her career. In 1950, O’Brien exhibited a significant number of County Mayo studies at the Watercolour Society of Ireland, which was followed by continuous participation in exhibitions at the RHA for many years. In 1951 O’Brien studied for a while at the Académie Montparnasse in Paris which encouraged her command of painting to develop, particularly with regards to colour. O’Brien served as president of the Watercolour Society of Ireland between the years 1962 and 1981. She also served as a council member of the Friends of the National Collections of Ireland. In 1976, O’Brien became a full Academician of the Royal Hibernian Academy. Her work is represented in the collection of the National Gallery of Ireland.