Amapá, ɗaya ne daga cikin jihohi 26 na Brazil. Yana cikin yankin Arewacin Brazil. Ita ce jiha ta biyu mafi ƙarancin yawan jama'a kuma jiha ta goma sha takwas mafi girma a yanki. Da yake a yankin arewa mai nisa na ƙasar, Amapá yana da iyaka da agogon Guiana ta arewa zuwa arewa, Tekun Atlantika daga gabas, Pará a kudu da yamma, da Suriname a arewa maso yamma. Babban birni kuma mafi girma shine Macapá. Jihar tana da kashi 0.4% na al'ummar Brazil kuma tana da alhakin kashi 0.22 kawai na GDP na Brazil[1].
A lokacin mulkin mallaka ana kiran yankin da sunan Portuguese Guiana kuma wani yanki ne na kasar Brazil ta Portugal. Daga baya, an bambanta yankin da sauran Guianas. Amapá ya kasance wani yanki na Pará, amma ya zama yanki na daban a cikin 1943, kuma jiha a cikin 1990.
↑"Estimativas da população residente nos municípios brasileiros com data de referência em 1º de julho de 2011" [Estimates of the Resident Population of Brazilian Municipalities as of July 1, 2011] (PDF) (in Portuguese). Brazilian Institute of Geography and Statistics. 30 August 2011. Retrieved 31 August 2011.