1st Army Corps

1st Army Corps may refer to:


 * I Army Corps (Greece)
 * I Army Corps (Wehrmacht)
 * I Corps (British India)
 * I Corps (India)
 * I Corps (Polish Armed Forces in the West)
 * I Corps (Sri Lanka)
 * I Corps (United Kingdom)
 * I Corps (United States)
 * 1st Army Corps (France)
 * 1st Army Corps (Russian Empire)
 * 1st Army Corps (Soviet Union)
 * 1st Army Corps (Armed Forces of South Russia)
 * 1st Army Corps (Azerbaijan)
 * 1st Army Corps (Armenia)
 * 1st Army Corps (Russia) (formerly the Donetsk People's Republic People's Militia, of Russian separatist forces in Donbas)