Karlsøya

Karlsøya or Karlsøy (Karl's island) may refer to:

Norway

 * Karlsøy Municipality, a municipality in Troms county
 * Karlsøy Church, a church in Karlsøy Municipality in Troms county
 * Karlsøy, Nordland, a village in Hamarøy municipality in Nordland county
 * Karlsøya (Møre og Romsdal), an island in Molde municipality, Møre og Romsdal county
 * Karlsøya (Nærøysund), an island in Nærøysund municipality, Trøndelag county
 * Karlsøya (Nordland), an island in Bodø municipality, Nordland county
 * Karlsøya (Ørland), an island in Ørland municipality, Trøndelag county
 * Karlsøya (Troms), an island in Karlsøy municipality, Troms county
 * Karlsøya (Østfold), an island in Sarpsborg municipality, Østfold county