The Palace of Truth is a three-act blank verse "Fairy Comedy" by W. S. Gilbert first produced at the Haymarket Theatre in London on 19 November 1870, adapted in significant part from Madame de Genlis's fairy story, Le Palais de Vérite. The play ran for approximately 140 performances and then toured the British provinces and enjoyed various revivals even well into the 20th century. There was also a New York production in 1910.

Sir William Schwenck Gilbert was an English dramatist, librettist, poet and illustrator best known for his collaboration with composer Arthur Sullivan, which produced fourteen comic operas. The most famous of these include H.M.S. Pinafore, The Pirates of Penzance and one of the most frequently performed works in the history of musical theatre, The Mikado. The popularity of these works was supported for over a century by year-round performances of them, in Britain and abroad, by the repertory company that Gilbert, Sullivan and their producer Richard D'Oyly Carte founded, the D'Oyly Carte Opera Company. These Savoy operas are still frequently performed in the English-speaking world and beyond.