The Cornelscourt Stakes is a Group 3 flat horse race in Ireland open to thoroughbred fillies ages three years and olders. It is run over a distance of 7 furlongs (1,408 metres) at Leopardstown in May.
The event was originally known as the Wassl Race and run over 1 mile. It was named after Wassl, the winner of the Irish 2,000 Guineas in 1983. For a period it held Listed status.
The name was changed to the Derrinstown Stud 1,000 Guineas Trial in 1990 when Derrinstown Stud began sponsoring the race. It was promoted to Group 3 level in 2002. In 2021 it was run without sponsorship as the Irish 1,000 Guineas Trial and it took on its present name in 2022. The race served as a trial for the Irish 1,000 Guineas. The last horse to win both races was Bethrah in 2010.
The race conditions changed in 2025 when the distance was reduced to 7 furlongs and the race was opened to older fillies.
Leading jockey since 1986 (5 wins):
Leading trainer since 1986 (9 wins):