Agistri, also Angistri or Agkistri (Greek: Αγκίστρι [aɲˈɟistɾi ~ aˈɟistɾi], English: "fishing hook"), is a small populated island and municipality in the Saronic Gulf in the Islands regional unit, Greece.

On this island with a land area of 13.367 km2 (5.161 sq mi),[3] there are only three settlements - Milos (Megalochori), Skala and Limenaria.

In 2011 it was recognized as a "green island" by the Prefecture of Piraeus and the National Technical University of Athens.

[6] Agistri is home to a wide variety of plants such as wild cyclamen, thyme, caper bushes, and thistles.

[7] The island also has a long history of free camping, though it is no longer allowed to erect tents in the forest due to fire hazard.

On 18 September 2015, Wall Street investor Brian Kelly announced he would be investing in the Nxt-based platform Drachmae, which has as its aim the revitalisation of the local economy of the Greek Island Agistri.