Megalomania is an obsession with power, wealth, fame, and a passion for grand schemes.

Megalomania or megalomaniac may also refer to:

• Grandiose delusions
• Narcissistic personality disorder
• Omnipotence (psychoanalysis), a stage of child development

• Megalomania (Aqua album), 2011
• Mania velichia or Megalomania, a 1985 album by Aria
• Megalomania (Enslavement of Beauty album), 2001
• Megalomania, a 2014 album by Kissin' Dynamite

• "Megalomaniac" (Incubus song), 2004
• "Megalomaniac" (KMFDM song), 1997
• "Megalomania", by Swedish stoner rock band Truckfighters and the band Firestone, from Fuzzsplit of the Century, 2003
• "Megalomaniac", by indietronica band +/- from You Are Here, 2003
• "Megalomania", by Skyhooks from Guilty Until Proven Insane , 1978
• "Megalomania", by Black Sabbath from Sabotage, 1975
• "Megalomania", by English punk band the Blood from False Gestures for a Devious Public, 1983
• "Megalomania", by Therion from Of Darkness..., 1991
• "Megalomania", by English indie rock band Pele from Fireworks, 1992
• "Megalomania", the boss music from the video game Live A Live, 1994
• "Megalomania", by English rock band Muse from Origin of Symmetry, 2001

• Mega-Lo-Mania, a 1991 real-time strategy game by Sensible Software

• "Megalovania", a 2008 song by Toby Fox used in several video games
• Delusions of grandeur (disambiguation)