Folie à deux (French for 'madness of two') is a rare psychiatric syndrome shared by two people.

Folie à deux may also refer to:

• "Folie à Deux" (short story), a story by Anirudh Kala from the 2018 anthology The Unsafe Asylum
• "Folie à Deux" (poem), a poem by Jill Alexander Essbaum from the 2007 poetry book Harlot (poetry collection)
• "Folie a Deux" (book), a 2013 autobiography by Robert Eringer

• Folie à Deux (album), a 2008 album by Fall Out Boy
• "Folie a Deux" (song), a 2005 song by Sezen Aksu off the album Excuse; see Sezen Aksu discography
• "Folie a Deux" (song), a chamber music composition by Emily Doolittle
• "Folie à Deux" (song), a 2024 song by Lady Gaga off her album Harlequin
• S.H.O.K.K. – Folie Á Deux

• "Folie à Deux" (Chicago Med), a 2018 season 3 episode 11 of Chicago Med
• "Folie à Deux" (Elementary), a 2016 season 5 episode 1 of Elementary
• "Folie a Deux" (Law & Order: Criminal Intent), a Law & Order: Criminal Intent season 8 episode
• "Folie à Deux" (The X-Files), a 1998 episode of The X-Files
• Joker: Folie à Deux, a 2024 sequel to the 2019 film Joker
• Folie a Deux (play), a 1995 stage play by Stephanie Johnson (author)

• Folie à Deux (winery), a Napa Valley, California, USA, winery
• Folie à Deux (exhibition), a 2018 art exhibition by Felix Bernstein & Gabe Rubin

• All pages with titles containing folie a deux
• Folie (disambiguation)
• Deux (disambiguation)