The Islands Regional Unit (Greek: Περιφερειακή ενότητα Νήσων, Periphereiaki enotita Nison) is one of the regional units of Greece.

The regional unit covers the Saronic Islands, a small part of the Peloponnese peninsula, and a few islands off the eastern Peloponnese coast.

The municipalities and provinces of Aigina, Agistri, Poros and Salamis was part of the Attica Prefecture and was created in 1833 as part of Attica and Boeotia Prefecture.

Cythera, Hydra, Spetses and Troizinia-Methana was originally part of Argolis and Korinthos prefecture until 1929, then part of Prefecture of Attica.

The regional unit of Islands was created as a part of the 2011 Kallikratis government reform.