Gaiety Theatre, Theatre venue on South King Street near St. Stephen's Green, Dublin, Ireland.

The Gaiety Theatre is a tan-brick theatre on South King Street, its facade banded with lighter stone and topped near the right corner by an illuminated red and yellow "GAIETY" sign. A glass and metal canopy on dark iron arched supports projects over the entrance, where dark doors sit between columns and arched windows, with rows of rectangular windows rising above.

Brothers John and Michael Gunn obtained a 21-year theatre licence in April 1871 and had Charles J. Phipps design the Gaiety, named after his 1868 London theatre. Built for £26,000 in 28 weeks, it opened on 27 November 1871 with She Stoops to Conquer. Frank Matcham extended it in 1883, and it remains Dublin's longest continuously producing theatre.

The Gaiety has staged an annual Christmas pantomime every year since December 1873, with only 2020 missed when The Little Mermaid was postponed to 2021. Its pantomimes cast Irish performers familiar to home audiences, including Fair City actors, and June Rodgers headlined them for years. The theatre also hosted the 1971 Eurovision Song Contest, the first staged in Ireland.

Each seating class has its own entrance and stairway, so check your ticket for the correct door before climbing. The theatre sits on South King Street off Grafton Street, a short walk from St. Stephen's Green. Stone staircases serve the upper levels; the entrance canopy shelters the doors on the street front.

Bronze handprints of legendary performers are cast into the pavement beneath the theatre's canopy, including opera singer Luciano Pavarotti and Irish comedian Brendan Grace. These marks honor artists whose careers were shaped by performing on this stage.