The Adelfoi Islets (, "brothers") are two Greek islands in the Sporades. They are located about east-southeast of the main island of Alonnisos and also administered by the municipality of the same main island name. The 2001 census reported a population of eleven inhabitants.
Its nearest islands and islets are Alonnisos and Peristera, Skantzoura to the east and Euboea further south.