P18

P18 may refer to:
 * P18 (band), a French electronic music group
 * CDKN2C, an enzyme
 * Gotland Regiment, of the Swedish Army
 * HMS Vagabond (P18), a submarine of the Royal Navy
 * Leukemia-associated phosphoprotein p18
 * Oxon Hill–Fort Washington Line, a bus route of the Washington Metropolitan Area Transit Authority
 * P-18 radar, a Soviet radar system
 * Papago Army Heliport, in Maricopa County, Arizona, United States
 * Papyrus 18, a biblical manuscript
 * Rogak P-18, a pistol